I
import
Unregistered / Unconfirmed
GUEST, unregistred user!
告诉我算法: 数学家们喜欢各种类型的有奇怪特性的数。例如,他们认为945是一个有趣的数,因为
它是第一个所有约数之和大于本身的奇数。
为了帮助他们寻找有趣的数,你将写一个程序扫描一定范围内的数,并确定在此范
围内约数个数最多的那个数。不幸的是,这个数和给定的范围的都比较较大,用简单的
方法寻找可能需要较多的运行时间。所以请确定你的算法能在几秒内完成最大范围内的
扫描。
输入格式
从文件divisors.in输入。文件只有一行,给出扫描的范围,由下界L和上界U确
定,满足2£ L £ U £ 1 000 000 000且0£ U - L £ 1 000 000。
输出格式
输出到文件divisors.out。对于给定的范围,输出该范围内约数个数D最多的数P。
若有多个,则输出最小的那个。请输出“Between L and U, P has a maximum of D
divisors.”,其中L, U, P和D的含义同前面所述。
/*
ACM Western European Region, 1994-95
Problem C, Divisors
Ed Karrels, October 1996
*/
#include <stdio.h>
#define nprimes 3402
int primes[] = {
2, 3, 5, 7, 11,
13, 17, 19, 23, 29,
31, 37, 41, 43, 47,
53, 59, 61, 67, 71,
73, 79, 83, 89, 97,
101, 103, 107, 109, 113,
127, 131, 137, 139, 149,
151, 157, 163, 167, 173,
179, 181, 191, 193, 197,
199, 211, 223, 227, 229,
233, 239, 241, 251, 257,
263, 269, 271, 277, 281,
283, 293, 307, 311, 313,
317, 331, 337, 347, 349,
353, 359, 367, 373, 379,
383, 389, 397, 401, 409,
419, 421, 431, 433, 439,
443, 449, 457, 461, 463,
467, 479, 487, 491, 499,
503, 509, 521, 523, 541,
547, 557, 563, 569, 571,
577, 587, 593, 599, 601,
607, 613, 617, 619, 631,
641, 643, 647, 653, 659,
661, 673, 677, 683, 691,
701, 709, 719, 727, 733,
739, 743, 751, 757, 761,
769, 773, 787, 797, 809,
811, 821, 823, 827, 829,
839, 853, 857, 859, 863,
877, 881, 883, 887, 907,
911, 919, 929, 937, 941,
947, 953, 967, 971, 977,
983, 991, 997, 1009, 1013,
1019, 1021, 1031, 1033, 1039,
1049, 1051, 1061, 1063, 1069,
1087, 1091, 1093, 1097, 1103,
1109, 1117, 1123, 1129, 1151,
1153, 1163, 1171, 1181, 1187,
1193, 1201, 1213, 1217, 1223,
1229, 1231, 1237, 1249, 1259,
1277, 1279, 1283, 1289, 1291,
1297, 1301, 1303, 1307, 1319,
1321, 1327, 1361, 1367, 1373,
1381, 1399, 1409, 1423, 1427,
1429, 1433, 1439, 1447, 1451,
1453, 1459, 1471, 1481, 1483,
1487, 1489, 1493, 1499, 1511,
1523, 1531, 1543, 1549, 1553,
1559, 1567, 1571, 1579, 1583,
1597, 1601, 1607, 1609, 1613,
1619, 1621, 1627, 1637, 1657,
1663, 1667, 1669, 1693, 1697,
1699, 1709, 1721, 1723, 1733,
1741, 1747, 1753, 1759, 1777,
1783, 1787, 1789, 1801, 1811,
1823, 1831, 1847, 1861, 1867,
1871, 1873, 1877, 1879, 1889,
1901, 1907, 1913, 1931, 1933,
1949, 1951, 1973, 1979, 1987,
1993, 1997, 1999, 2003, 2011,
2017, 2027, 2029, 2039, 2053,
2063, 2069, 2081, 2083, 2087,
2089, 2099, 2111, 2113, 2129,
2131, 2137, 2141, 2143, 2153,
2161, 2179, 2203, 2207, 2213,
2221, 2237, 2239, 2243, 2251,
2267, 2269, 2273, 2281, 2287,
2293, 2297, 2309, 2311, 2333,
2339, 2341, 2347, 2351, 2357,
2371, 2377, 2381, 2383, 2389,
2393, 2399, 2411, 2417, 2423,
2437, 2441, 2447, 2459, 2467,
2473, 2477, 2503, 2521, 2531,
2539, 2543, 2549, 2551, 2557,
2579, 2591, 2593, 2609, 2617,
2621, 2633, 2647, 2657, 2659,
2663, 2671, 2677, 2683, 2687,
2689, 2693, 2699, 2707, 2711,
2713, 2719, 2729, 2731, 2741,
2749, 2753, 2767, 2777, 2789,
2791, 2797, 2801, 2803, 2819,
2833, 2837, 2843, 2851, 2857,
2861, 2879, 2887, 2897, 2903,
2909, 2917, 2927, 2939, 2953,
2957, 2963, 2969, 2971, 2999,
3001, 3011, 3019, 3023, 3037,
3041, 3049, 3061, 3067, 3079,
3083, 3089, 3109, 3119, 3121,
3137, 3163, 3167, 3169, 3181,
3187, 3191, 3203, 3209, 3217,
3221, 3229, 3251, 3253, 3257,
3259, 3271, 3299, 3301, 3307,
3313, 3319, 3323, 3329, 3331,
3343, 3347, 3359, 3361, 3371,
3373, 3389, 3391, 3407, 3413,
3433, 3449, 3457, 3461, 3463,
3467, 3469, 3491, 3499, 3511,
3517, 3527, 3529, 3533, 3539,
3541, 3547, 3557, 3559, 3571,
3581, 3583, 3593, 3607, 3613,
3617, 3623, 3631, 3637, 3643,
3659, 3671, 3673, 3677, 3691,
3697, 3701, 3709, 3719, 3727,
3733, 3739, 3761, 3767, 3769,
3779, 3793, 3797, 3803, 3821,
3823, 3833, 3847, 3851, 3853,
3863, 3877, 3881, 3889, 3907,
3911, 3917, 3919, 3923, 3929,
3931, 3943, 3947, 3967, 3989,
4001, 4003, 4007, 4013, 4019,
4021, 4027, 4049, 4051, 4057,
4073, 4079, 4091, 4093, 4099,
4111, 4127, 4129, 4133, 4139,
4153, 4157, 4159, 4177, 4201,
4211, 4217, 4219, 4229, 4231,
4241, 4243, 4253, 4259, 4261,
4271, 4273, 4283, 4289, 4297,
4327, 4337, 4339, 4349, 4357,
4363, 4373, 4391, 4397, 4409,
4421, 4423, 4441, 4447, 4451,
4457, 4463, 4481, 4483, 4493,
4507, 4513, 4517, 4519, 4523,
4547, 4549, 4561, 4567, 4583,
4591, 4597, 4603, 4621, 4637,
4639, 4643, 4649, 4651, 4657,
4663, 4673, 4679, 4691, 4703,
4721, 4723, 4729, 4733, 4751,
4759, 4783, 4787, 4789, 4793,
4799, 4801, 4813, 4817, 4831,
4861, 4871, 4877, 4889, 4903,
4909, 4919, 4931, 4933, 4937,
4943, 4951, 4957, 4967, 4969,
4973, 4987, 4993, 4999, 5003,
5009, 5011, 5021, 5023, 5039,
5051, 5059, 5077, 5081, 5087,
5099, 5101, 5107, 5113, 5119,
5147, 5153, 5167, 5171, 5179,
5189, 5197, 5209, 5227, 5231,
5233, 5237, 5261, 5273, 5279,
5281, 5297, 5303, 5309, 5323,
5333, 5347, 5351, 5381, 5387,
5393, 5399, 5407, 5413, 5417,
5419, 5431, 5437, 5441, 5443,
5449, 5471, 5477, 5479, 5483,
5501, 5503, 5507, 5519, 5521,
5527, 5531, 5557, 5563, 5569,
5573, 5581, 5591, 5623, 5639,
5641, 5647, 5651, 5653, 5657,
5659, 5669, 5683, 5689, 5693,
5701, 5711, 5717, 5737, 5741,
5743, 5749, 5779, 5783, 5791,
5801, 5807, 5813, 5821, 5827,
5839, 5843, 5849, 5851, 5857,
5861, 5867, 5869, 5879, 5881,
5897, 5903, 5923, 5927, 5939,
5953, 5981, 5987, 6007, 6011,
6029, 6037, 6043, 6047, 6053,
6067, 6073, 6079, 6089, 6091,
6101, 6113, 6121, 6131, 6133,
6143, 6151, 6163, 6173, 6197,
6199, 6203, 6211, 6217, 6221,
6229, 6247, 6257, 6263, 6269,
6271, 6277, 6287, 6299, 6301,
6311, 6317, 6323, 6329, 6337,
6343, 6353, 6359, 6361, 6367,
6373, 6379, 6389, 6397, 6421,
6427, 6449, 6451, 6469, 6473,
6481, 6491, 6521, 6529, 6547,
6551, 6553, 6563, 6569, 6571,
6577, 6581, 6599, 6607, 6619,
6637, 6653, 6659, 6661, 6673,
6679, 6689, 6691, 6701, 6703,
6709, 6719, 6733, 6737, 6761,
6763, 6779, 6781, 6791, 6793,
6803, 6823, 6827, 6829, 6833,
6841, 6857, 6863, 6869, 6871,
6883, 6899, 6907, 6911, 6917,
6947, 6949, 6959, 6961, 6967,
6971, 6977, 6983, 6991, 6997,
7001, 7013, 7019, 7027, 7039,
7043, 7057, 7069, 7079, 7103,
7109, 7121, 7127, 7129, 7151,
7159, 7177, 7187, 7193, 7207,
7211, 7213, 7219, 7229, 7237,
7243, 7247, 7253, 7283, 7297,
7307, 7309, 7321, 7331, 7333,
7349, 7351, 7369, 7393, 7411,
7417, 7433, 7451, 7457, 7459,
7477, 7481, 7487, 7489, 7499,
7507, 7517, 7523, 7529, 7537,
7541, 7547, 7549, 7559, 7561,
7573, 7577, 7583, 7589, 7591,
7603, 7607, 7621, 7639, 7643,
7649, 7669, 7673, 7681, 7687,
7691, 7699, 7703, 7717, 7723,
7727, 7741, 7753, 7757, 7759,
7789, 7793, 7817, 7823, 7829,
7841, 7853, 7867, 7873, 7877,
7879, 7883, 7901, 7907, 7919,
7927, 7933, 7937, 7949, 7951,
7963, 7993, 8009, 8011, 8017,
8039, 8053, 8059, 8069, 8081,
8087, 8089, 8093, 8101, 8111,
8117, 8123, 8147, 8161, 8167,
8171, 8179, 8191, 8209, 8219,
8221, 8231, 8233, 8237, 8243,
8263, 8269, 8273, 8287, 8291,
8293, 8297, 8311, 8317, 8329,
8353, 8363, 8369, 8377, 8387,
8389, 8419, 8423, 8429, 8431,
8443, 8447, 8461, 8467, 8501,
8513, 8521, 8527, 8537, 8539,
8543, 8563, 8573, 8581, 8597,
8599, 8609, 8623, 8627, 8629,
8641, 8647, 8663, 8669, 8677,
8681, 8689, 8693, 8699, 8707,
8713, 8719, 8731, 8737, 8741,
8747, 8753, 8761, 8779, 8783,
8803, 8807, 8819, 8821, 8831,
8837, 8839, 8849, 8861, 8863,
8867, 8887, 8893, 8923, 8929,
8933, 8941, 8951, 8963, 8969,
8971, 8999, 9001, 9007, 9011,
9013, 9029, 9041, 9043, 9049,
9059, 9067, 9091, 9103, 9109,
9127, 9133, 9137, 9151, 9157,
9161, 9173, 9181, 9187, 9199,
9203, 9209, 9221, 9227, 9239,
9241, 9257, 9277, 9281, 9283,
9293, 9311, 9319, 9323, 9337,
9341, 9343, 9349, 9371, 9377,
9391, 9397, 9403, 9413, 9419,
9421, 9431, 9433, 9437, 9439,
9461, 9463, 9467, 9473, 9479,
9491, 9497, 9511, 9521, 9533,
9539, 9547, 9551, 9587, 9601,
9613, 9619, 9623, 9629, 9631,
9643, 9649, 9661, 9677, 9679,
9689, 9697, 9719, 9721, 9733,
9739, 9743, 9749, 9767, 9769,
9781, 9787, 9791, 9803, 9811,
9817, 9829, 9833, 9839, 9851,
9857, 9859, 9871, 9883, 9887,
9901, 9907, 9923, 9929, 9931,
9941, 9949, 9967, 9973, 10007,
10009, 10037, 10039, 10061, 10067,
10069, 10079, 10091, 10093, 10099,
10103, 10111, 10133, 10139, 10141,
10151, 10159, 10163, 10169, 10177,
10181, 10193, 10211, 10223, 10243,
10247, 10253, 10259, 10267, 10271,
10273, 10289, 10301, 10303, 10313,
10321, 10331, 10333, 10337, 10343,
10357, 10369, 10391, 10399, 10427,
10429, 10433, 10453, 10457, 10459,
10463, 10477, 10487, 10499, 10501,
10513, 10529, 10531, 10559, 10567,
10589, 10597, 10601, 10607, 10613,
10627, 10631, 10639, 10651, 10657,
10663, 10667, 10687, 10691, 10709,
10711, 10723, 10729, 10733, 10739,
10753, 10771, 10781, 10789, 10799,
10831, 10837, 10847, 10853, 10859,
10861, 10867, 10883, 10889, 10891,
10903, 10909, 10937, 10939, 10949,
10957, 10973, 10979, 10987, 10993,
11003, 11027, 11047, 11057, 11059,
11069, 11071, 11083, 11087, 11093,
11113, 11117, 11119, 11131, 11149,
11159, 11161, 11171, 11173, 11177,
11197, 11213, 11239, 11243, 11251,
11257, 11261, 11273, 11279, 11287,
11299, 11311, 11317, 11321, 11329,
11351, 11353, 11369, 11383, 11393,
11399, 11411, 11423, 11437, 11443,
11447, 11467, 11471, 11483, 11489,
11491, 11497, 11503, 11519, 11527,
11549, 11551, 11579, 11587, 11593,
11597, 11617, 11621, 11633, 11657,
11677, 11681, 11689, 11699, 11701,
11717, 11719, 11731, 11743, 11777,
11779, 11783, 11789, 11801, 11807,
11813, 11821, 11827, 11831, 11833,
11839, 11863, 11867, 11887, 11897,
11903, 11909, 11923, 11927, 11933,
11939, 11941, 11953, 11959, 11969,
11971, 11981, 11987, 12007, 12011,
12037, 12041, 12043, 12049, 12071,
12073, 12097, 12101, 12107, 12109,
12113, 12119, 12143, 12149, 12157,
12161, 12163, 12197, 12203, 12211,
12227, 12239, 12241, 12251, 12253,
12263, 12269, 12277, 12281, 12289,
12301, 12323, 12329, 12343, 12347,
12373, 12377, 12379, 12391, 12401,
12409, 12413, 12421, 12433, 12437,
12451, 12457, 12473, 12479, 12487,
12491, 12497, 12503, 12511, 12517,
12527, 12539, 12541, 12547, 12553,
12569, 12577, 12583, 12589, 12601,
12611, 12613, 12619, 12637, 12641,
12647, 12653, 12659, 12671, 12689,
12697, 12703, 12713, 12721, 12739,
12743, 12757, 12763, 12781, 12791,
12799, 12809, 12821, 12823, 12829,
12841, 12853, 12889, 12893, 12899,
12907, 12911, 12917, 12919, 12923,
12941, 12953, 12959, 12967, 12973,
12979, 12983, 13001, 13003, 13007,
13009, 13033, 13037, 13043, 13049,
13063, 13093, 13099, 13103, 13109,
13121, 13127, 13147, 13151, 13159,
13163, 13171, 13177, 13183, 13187,
13217, 13219, 13229, 13241, 13249,
13259, 13267, 13291, 13297, 13309,
13313, 13327, 13331, 13337, 13339,
13367, 13381, 13397, 13399, 13411,
13417, 13421, 13441, 13451, 13457,
13463, 13469, 13477, 13487, 13499,
13513, 13523, 13537, 13553, 13567,
13577, 13591, 13597, 13613, 13619,
13627, 13633, 13649, 13669, 13679,
13681, 13687, 13691, 13693, 13697,
13709, 13711, 13721, 13723, 13729,
13751, 13757, 13759, 13763, 13781,
13789, 13799, 13807, 13829, 13831,
13841, 13859, 13873, 13877, 13879,
13883, 13901, 13903, 13907, 13913,
13921, 13931, 13933, 13963, 13967,
13997, 13999, 14009, 14011, 14029,
14033, 14051, 14057, 14071, 14081,
14083, 14087, 14107, 14143, 14149,
14153, 14159, 14173, 14177, 14197,
14207, 14221, 14243, 14249, 14251,
14281, 14293, 14303, 14321, 14323,
14327, 14341, 14347, 14369, 14387,
14389, 14401, 14407, 14411, 14419,
14423, 14431, 14437, 14447, 14449,
14461, 14479, 14489, 14503, 14519,
14533, 14537, 14543, 14549, 14551,
14557, 14561, 14563, 14591, 14593,
14621, 14627, 14629, 14633, 14639,
14653, 14657, 14669, 14683, 14699,
14713, 14717, 14723, 14731, 14737,
14741, 14747, 14753, 14759, 14767,
14771, 14779, 14783, 14797, 14813,
14821, 14827, 14831, 14843, 14851,
14867, 14869, 14879, 14887, 14891,
14897, 14923, 14929, 14939, 14947,
14951, 14957, 14969, 14983, 15013,
15017, 15031, 15053, 15061, 15073,
15077, 15083, 15091, 15101, 15107,
15121, 15131, 15137, 15139, 15149,
15161, 15173, 15187, 15193, 15199,
15217, 15227, 15233, 15241, 15259,
15263, 15269, 15271, 15277, 15287,
15289, 15299, 15307, 15313, 15319,
15329, 15331, 15349, 15359, 15361,
15373, 15377, 15383, 15391, 15401,
15413, 15427, 15439, 15443, 15451,
15461, 15467, 15473, 15493, 15497,
15511, 15527, 15541, 15551, 15559,
15569, 15581, 15583, 15601, 15607,
15619, 15629, 15641, 15643, 15647,
15649, 15661, 15667, 15671, 15679,
15683, 15727, 15731, 15733, 15737,
15739, 15749, 15761, 15767, 15773,
15787, 15791, 15797, 15803, 15809,
15817, 15823, 15859, 15877, 15881,
15887, 15889, 15901, 15907, 15913,
15919, 15923, 15937, 15959, 15971,
15973, 15991, 16001, 16007, 16033,
16057, 16061, 16063, 16067, 16069,
16073, 16087, 16091, 16097, 16103,
16111, 16127, 16139, 16141, 16183,
16187, 16189, 16193, 16217, 16223,
16229, 16231, 16249, 16253, 16267,
16273, 16301, 16319, 16333, 16339,
16349, 16361, 16363, 16369, 16381,
16411, 16417, 16421, 16427, 16433,
16447, 16451, 16453, 16477, 16481,
16487, 16493, 16519, 16529, 16547,
16553, 16561, 16567, 16573, 16603,
16607, 16619, 16631, 16633, 16649,
16651, 16657, 16661, 16673, 16691,
16693, 16699, 16703, 16729, 16741,
16747, 16759, 16763, 16787, 16811,
16823, 16829, 16831, 16843, 16871,
16879, 16883, 16889, 16901, 16903,
16921, 16927, 16931, 16937, 16943,
16963, 16979, 16981, 16987, 16993,
17011, 17021, 17027, 17029, 17033,
17041, 17047, 17053, 17077, 17093,
17099, 17107, 17117, 17123, 17137,
17159, 17167, 17183, 17189, 17191,
17203, 17207, 17209, 17231, 17239,
17257, 17291, 17293, 17299, 17317,
17321, 17327, 17333, 17341, 17351,
17359, 17377, 17383, 17387, 17389,
17393, 17401, 17417, 17419, 17431,
17443, 17449, 17467, 17471, 17477,
17483, 17489, 17491, 17497, 17509,
17519, 17539, 17551, 17569, 17573,
17579, 17581, 17597, 17599, 17609,
17623, 17627, 17657, 17659, 17669,
17681, 17683, 17707, 17713, 17729,
17737, 17747, 17749, 17761, 17783,
17789, 17791, 17807, 17827, 17837,
17839, 17851, 17863, 17881, 17891,
17903, 17909, 17911, 17921, 17923,
17929, 17939, 17957, 17959, 17971,
17977, 17981, 17987, 17989, 18013,
18041, 18043, 18047, 18049, 18059,
18061, 18077, 18089, 18097, 18119,
18121, 18127, 18131, 18133, 18143,
18149, 18169, 18181, 18191, 18199,
18211, 18217, 18223, 18229, 18233,
18251, 18253, 18257, 18269, 18287,
18289, 18301, 18307, 18311, 18313,
18329, 18341, 18353, 18367, 18371,
18379, 18397, 18401, 18413, 18427,
18433, 18439, 18443, 18451, 18457,
18461, 18481, 18493, 18503, 18517,
18521, 18523, 18539, 18541, 18553,
18583, 18587, 18593, 18617, 18637,
18661, 18671, 18679, 18691, 18701,
18713, 18719, 18731, 18743, 18749,
18757, 18773, 18787, 18793, 18797,
18803, 18839, 18859, 18869, 18899,
18911, 18913, 18917, 18919, 18947,
18959, 18973, 18979, 19001, 19009,
19013, 19031, 19037, 19051, 19069,
19073, 19079, 19081, 19087, 19121,
19139, 19141, 19157, 19163, 19181,
19183, 19207, 19211, 19213, 19219,
19231, 19237, 19249, 19259, 19267,
19273, 19289, 19301, 19309, 19319,
19333, 19373, 19379, 19381, 19387,
19391, 19403, 19417, 19421, 19423,
19427, 19429, 19433, 19441, 19447,
19457, 19463, 19469, 19471, 19477,
19483, 19489, 19501, 19507, 19531,
19541, 19543, 19553, 19559, 19571,
19577, 19583, 19597, 19603, 19609,
19661, 19681, 19687, 19697, 19699,
19709, 19717, 19727, 19739, 19751,
19753, 19759, 19763, 19777, 19793,
19801, 19813, 19819, 19841, 19843,
19853, 19861, 19867, 19889, 19891,
19913, 19919, 19927, 19937, 19949,
19961, 19963, 19973, 19979, 19991,
19993, 19997, 20011, 20021, 20023,
20029, 20047, 20051, 20063, 20071,
20089, 20101, 20107, 20113, 20117,
20123, 20129, 20143, 20147, 20149,
20161, 20173, 20177, 20183, 20201,
20219, 20231, 20233, 20249, 20261,
20269, 20287, 20297, 20323, 20327,
20333, 20341, 20347, 20353, 20357,
20359, 20369, 20389, 20393, 20399,
20407, 20411, 20431, 20441, 20443,
20477, 20479, 20483, 20507, 20509,
20521, 20533, 20543, 20549, 20551,
20563, 20593, 20599, 20611, 20627,
20639, 20641, 20663, 20681, 20693,
20707, 20717, 20719, 20731, 20743,
20747, 20749, 20753, 20759, 20771,
20773, 20789, 20807, 20809, 20849,
20857, 20873, 20879, 20887, 20897,
20899, 20903, 20921, 20929, 20939,
20947, 20959, 20963, 20981, 20983,
21001, 21011, 21013, 21017, 21019,
21023, 21031, 21059, 21061, 21067,
21089, 21101, 21107, 21121, 21139,
21143, 21149, 21157, 21163, 21169,
21179, 21187, 21191, 21193, 21211,
21221, 21227, 21247, 21269, 21277,
21283, 21313, 21317, 21319, 21323,
21341, 21347, 21377, 21379, 21383,
21391, 21397, 21401, 21407, 21419,
21433, 21467, 21481, 21487, 21491,
21493, 21499, 21503, 21517, 21521,
21523, 21529, 21557, 21559, 21563,
21569, 21577, 21587, 21589, 21599,
21601, 21611, 21613, 21617, 21647,
21649, 21661, 21673, 21683, 21701,
21713, 21727, 21737, 21739, 21751,
21757, 21767, 21773, 21787, 21799,
21803, 21817, 21821, 21839, 21841,
21851, 21859, 21863, 21871, 21881,
21893, 21911, 21929, 21937, 21943,
21961, 21977, 21991, 21997, 22003,
22013, 22027, 22031, 22037, 22039,
22051, 22063, 22067, 22073, 22079,
22091, 22093, 22109, 22111, 22123,
22129, 22133, 22147, 22153, 22157,
22159, 22171, 22189, 22193, 22229,
22247, 22259, 22271, 22273, 22277,
22279, 22283, 22291, 22303, 22307,
22343, 22349, 22367, 22369, 22381,
22391, 22397, 22409, 22433, 22441,
22447, 22453, 22469, 22481, 22483,
22501, 22511, 22531, 22541, 22543,
22549, 22567, 22571, 22573, 22613,
22619, 22621, 22637, 22639, 22643,
22651, 22669, 22679, 22691, 22697,
22699, 22709, 22717, 22721, 22727,
22739, 22741, 22751, 22769, 22777,
22783, 22787, 22807, 22811, 22817,
22853, 22859, 22861, 22871, 22877,
22901, 22907, 22921, 22937, 22943,
22961, 22963, 22973, 22993, 23003,
23011, 23017, 23021, 23027, 23029,
23039, 23041, 23053, 23057, 23059,
23063, 23071, 23081, 23087, 23099,
23117, 23131, 23143, 23159, 23167,
23173, 23189, 23197, 23201, 23203,
23209, 23227, 23251, 23269, 23279,
23291, 23293, 23297, 23311, 23321,
23327, 23333, 23339, 23357, 23369,
23371, 23399, 23417, 23431, 23447,
23459, 23473, 23497, 23509, 23531,
23537, 23539, 23549, 23557, 23561,
23563, 23567, 23581, 23593, 23599,
23603, 23609, 23623, 23627, 23629,
23633, 23663, 23669, 23671, 23677,
23687, 23689, 23719, 23741, 23743,
23747, 23753, 23761, 23767, 23773,
23789, 23801, 23813, 23819, 23827,
23831, 23833, 23857, 23869, 23873,
23879, 23887, 23893, 23899, 23909,
23911, 23917, 23929, 23957, 23971,
23977, 23981, 23993, 24001, 24007,
24019, 24023, 24029, 24043, 24049,
24061, 24071, 24077, 24083, 24091,
24097, 24103, 24107, 24109, 24113,
24121, 24133, 24137, 24151, 24169,
24179, 24181, 24197, 24203, 24223,
24229, 24239, 24247, 24251, 24281,
24317, 24329, 24337, 24359, 24371,
24373, 24379, 24391, 24407, 24413,
24419, 24421, 24439, 24443, 24469,
24473, 24481, 24499, 24509, 24517,
24527, 24533, 24547, 24551, 24571,
24593, 24611, 24623, 24631, 24659,
24671, 24677, 24683, 24691, 24697,
24709, 24733, 24749, 24763, 24767,
24781, 24793, 24799, 24809, 24821,
24841, 24847, 24851, 24859, 24877,
24889, 24907, 24917, 24919, 24923,
24943, 24953, 24967, 24971, 24977,
24979, 24989, 25013, 25031, 25033,
25037, 25057, 25073, 25087, 25097,
25111, 25117, 25121, 25127, 25147,
25153, 25163, 25169, 25171, 25183,
25189, 25219, 25229, 25237, 25243,
25247, 25253, 25261, 25301, 25303,
25307, 25309, 25321, 25339, 25343,
25349, 25357, 25367, 25373, 25391,
25409, 25411, 25423, 25439, 25447,
25453, 25457, 25463, 25469, 25471,
25523, 25537, 25541, 25561, 25577,
25579, 25583, 25589, 25601, 25603,
25609, 25621, 25633, 25639, 25643,
25657, 25667, 25673, 25679, 25693,
25703, 25717, 25733, 25741, 25747,
25759, 25763, 25771, 25793, 25799,
25801, 25819, 25841, 25847, 25849,
25867, 25873, 25889, 25903, 25913,
25919, 25931, 25933, 25939, 25943,
25951, 25969, 25981, 25997, 25999,
26003, 26017, 26021, 26029, 26041,
26053, 26083, 26099, 26107, 26111,
26113, 26119, 26141, 26153, 26161,
26171, 26177, 26183, 26189, 26203,
26209, 26227, 26237, 26249, 26251,
26261, 26263, 26267, 26293, 26297,
26309, 26317, 26321, 26339, 26347,
26357, 26371, 26387, 26393, 26399,
26407, 26417, 26423, 26431, 26437,
26449, 26459, 26479, 26489, 26497,
26501, 26513, 26539, 26557, 26561,
26573, 26591, 26597, 26627, 26633,
26641, 26647, 26669, 26681, 26683,
26687, 26693, 26699, 26701, 26711,
26713, 26717, 26723, 26729, 26731,
26737, 26759, 26777, 26783, 26801,
26813, 26821, 26833, 26839, 26849,
26861, 26863, 26879, 26881, 26891,
26893, 26903, 26921, 26927, 26947,
26951, 26953, 26959, 26981, 26987,
26993, 27011, 27017, 27031, 27043,
27059, 27061, 27067, 27073, 27077,
27091, 27103, 27107, 27109, 27127,
27143, 27179, 27191, 27197, 27211,
27239, 27241, 27253, 27259, 27271,
27277, 27281, 27283, 27299, 27329,
27337, 27361, 27367, 27397, 27407,
27409, 27427, 27431, 27437, 27449,
27457, 27479, 27481, 27487, 27509,
27527, 27529, 27539, 27541, 27551,
27581, 27583, 27611, 27617, 27631,
27647, 27653, 27673, 27689, 27691,
27697, 27701, 27733, 27737, 27739,
27743, 27749, 27751, 27763, 27767,
27773, 27779, 27791, 27793, 27799,
27803, 27809, 27817, 27823, 27827,
27847, 27851, 27883, 27893, 27901,
27917, 27919, 27941, 27943, 27947,
27953, 27961, 27967, 27983, 27997,
28001, 28019, 28027, 28031, 28051,
28057, 28069, 28081, 28087, 28097,
28099, 28109, 28111, 28123, 28151,
28163, 28181, 28183, 28201, 28211,
28219, 28229, 28277, 28279, 28283,
28289, 28297, 28307, 28309, 28319,
28349, 28351, 28387, 28393, 28403,
28409, 28411, 28429, 28433, 28439,
28447, 28463, 28477, 28493, 28499,
28513, 28517, 28537, 28541, 28547,
28549, 28559, 28571, 28573, 28579,
28591, 28597, 28603, 28607, 28619,
28621, 28627, 28631, 28643, 28649,
28657, 28661, 28663, 28669, 28687,
28697, 28703, 28711, 28723, 28729,
28751, 28753, 28759, 28771, 28789,
28793, 28807, 28813, 28817, 28837,
28843, 28859, 28867, 28871, 28879,
28901, 28909, 28921, 28927, 28933,
28949, 28961, 28979, 29009, 29017,
29021, 29023, 29027, 29033, 29059,
29063, 29077, 29101, 29123, 29129,
29131, 29137, 29147, 29153, 29167,
29173, 29179, 29191, 29201, 29207,
29209, 29221, 29231, 29243, 29251,
29269, 29287, 29297, 29303, 29311,
29327, 29333, 29339, 29347, 29363,
29383, 29387, 29389, 29399, 29401,
29411, 29423, 29429, 29437, 29443,
29453, 29473, 29483, 29501, 29527,
29531, 29537, 29567, 29569, 29573,
29581, 29587, 29599, 29611, 29629,
29633, 29641, 29663, 29669, 29671,
29683, 29717, 29723, 29741, 29753,
29759, 29761, 29789, 29803, 29819,
29833, 29837, 29851, 29863, 29867,
29873, 29879, 29881, 29917, 29921,
29927, 29947, 29959, 29983, 29989,
30011, 30013, 30029, 30047, 30059,
30071, 30089, 30091, 30097, 30103,
30109, 30113, 30119, 30133, 30137,
30139, 30161, 30169, 30181, 30187,
30197, 30203, 30211, 30223, 30241,
30253, 30259, 30269, 30271, 30293,
30307, 30313, 30319, 30323, 30341,
30347, 30367, 30389, 30391, 30403,
30427, 30431, 30449, 30467, 30469,
30491, 30493, 30497, 30509, 30517,
30529, 30539, 30553, 30557, 30559,
30577, 30593, 30631, 30637, 30643,
30649, 30661, 30671, 30677, 30689,
30697, 30703, 30707, 30713, 30727,
30757, 30763, 30773, 30781, 30803,
30809, 30817, 30829, 30839, 30841,
30851, 30853, 30859, 30869, 30871,
30881, 30893, 30911, 30931, 30937,
30941, 30949, 30971, 30977, 30983,
31013, 31019, 31033, 31039, 31051,
31063, 31069, 31079, 31081, 31091,
31121, 31123, 31139, 31147, 31151,
31153, 31159, 31177, 31181, 31183,
31189, 31193, 31219, 31223, 31231,
31237, 31247, 31249, 31253, 31259,
31267, 31271, 31277, 31307, 31319,
31321, 31327, 31333, 31337, 31357,
31379, 31387, 31391, 31393, 31397,
31469, 31477, 31481, 31489, 31511,
31513, 31517, 31531, 31541, 31543,
31547, 31567, 31573, 31583, 31601,
31607, 31627
};
int NumDivisors(long num) {
int factors[nprimes];
int i, nd=1, p, pn;
for (i=0; i<nprimes; i++) factors = 1;
pn = 0;
p = primes[0];
/* factor the number, keeping track of how many times
each prime can be divided into it */
while (p*p <= num) {
if (!(num % p)) {
do {
factors[pn]++;
num /= p;
} while (!(num % p));
} else {
p = primes[++pn];
}
}
if (num > 1) {
nd *= 2;
}
/* if the number is a^i * b^j * c^k * ...,
then it has (i+1)(j+1)(k+1)... divisors. */
for (i=0; i<=pn; i++) {
nd *= factors;
}
return nd;
}
int main() {
int i, n, nd, max_nd;
long lo, hi, best, count;
scanf("%d", &n);
for (i=0; i<n; i++) {
scanf("%ld %ld", &lo, &hi);
max_nd = 0;
for (count = lo; count<=hi; count++) {
nd = NumDivisors(count);
if (nd > max_nd) {
max_nd = nd;
best = count;
}
}
printf("Between %ld and %ld, %ld has a maximum of %d divisors.",
lo, hi, best, max_nd);
}
return 0;
}
它是第一个所有约数之和大于本身的奇数。
为了帮助他们寻找有趣的数,你将写一个程序扫描一定范围内的数,并确定在此范
围内约数个数最多的那个数。不幸的是,这个数和给定的范围的都比较较大,用简单的
方法寻找可能需要较多的运行时间。所以请确定你的算法能在几秒内完成最大范围内的
扫描。
输入格式
从文件divisors.in输入。文件只有一行,给出扫描的范围,由下界L和上界U确
定,满足2£ L £ U £ 1 000 000 000且0£ U - L £ 1 000 000。
输出格式
输出到文件divisors.out。对于给定的范围,输出该范围内约数个数D最多的数P。
若有多个,则输出最小的那个。请输出“Between L and U, P has a maximum of D
divisors.”,其中L, U, P和D的含义同前面所述。
/*
ACM Western European Region, 1994-95
Problem C, Divisors
Ed Karrels, October 1996
*/
#include <stdio.h>
#define nprimes 3402
int primes[] = {
2, 3, 5, 7, 11,
13, 17, 19, 23, 29,
31, 37, 41, 43, 47,
53, 59, 61, 67, 71,
73, 79, 83, 89, 97,
101, 103, 107, 109, 113,
127, 131, 137, 139, 149,
151, 157, 163, 167, 173,
179, 181, 191, 193, 197,
199, 211, 223, 227, 229,
233, 239, 241, 251, 257,
263, 269, 271, 277, 281,
283, 293, 307, 311, 313,
317, 331, 337, 347, 349,
353, 359, 367, 373, 379,
383, 389, 397, 401, 409,
419, 421, 431, 433, 439,
443, 449, 457, 461, 463,
467, 479, 487, 491, 499,
503, 509, 521, 523, 541,
547, 557, 563, 569, 571,
577, 587, 593, 599, 601,
607, 613, 617, 619, 631,
641, 643, 647, 653, 659,
661, 673, 677, 683, 691,
701, 709, 719, 727, 733,
739, 743, 751, 757, 761,
769, 773, 787, 797, 809,
811, 821, 823, 827, 829,
839, 853, 857, 859, 863,
877, 881, 883, 887, 907,
911, 919, 929, 937, 941,
947, 953, 967, 971, 977,
983, 991, 997, 1009, 1013,
1019, 1021, 1031, 1033, 1039,
1049, 1051, 1061, 1063, 1069,
1087, 1091, 1093, 1097, 1103,
1109, 1117, 1123, 1129, 1151,
1153, 1163, 1171, 1181, 1187,
1193, 1201, 1213, 1217, 1223,
1229, 1231, 1237, 1249, 1259,
1277, 1279, 1283, 1289, 1291,
1297, 1301, 1303, 1307, 1319,
1321, 1327, 1361, 1367, 1373,
1381, 1399, 1409, 1423, 1427,
1429, 1433, 1439, 1447, 1451,
1453, 1459, 1471, 1481, 1483,
1487, 1489, 1493, 1499, 1511,
1523, 1531, 1543, 1549, 1553,
1559, 1567, 1571, 1579, 1583,
1597, 1601, 1607, 1609, 1613,
1619, 1621, 1627, 1637, 1657,
1663, 1667, 1669, 1693, 1697,
1699, 1709, 1721, 1723, 1733,
1741, 1747, 1753, 1759, 1777,
1783, 1787, 1789, 1801, 1811,
1823, 1831, 1847, 1861, 1867,
1871, 1873, 1877, 1879, 1889,
1901, 1907, 1913, 1931, 1933,
1949, 1951, 1973, 1979, 1987,
1993, 1997, 1999, 2003, 2011,
2017, 2027, 2029, 2039, 2053,
2063, 2069, 2081, 2083, 2087,
2089, 2099, 2111, 2113, 2129,
2131, 2137, 2141, 2143, 2153,
2161, 2179, 2203, 2207, 2213,
2221, 2237, 2239, 2243, 2251,
2267, 2269, 2273, 2281, 2287,
2293, 2297, 2309, 2311, 2333,
2339, 2341, 2347, 2351, 2357,
2371, 2377, 2381, 2383, 2389,
2393, 2399, 2411, 2417, 2423,
2437, 2441, 2447, 2459, 2467,
2473, 2477, 2503, 2521, 2531,
2539, 2543, 2549, 2551, 2557,
2579, 2591, 2593, 2609, 2617,
2621, 2633, 2647, 2657, 2659,
2663, 2671, 2677, 2683, 2687,
2689, 2693, 2699, 2707, 2711,
2713, 2719, 2729, 2731, 2741,
2749, 2753, 2767, 2777, 2789,
2791, 2797, 2801, 2803, 2819,
2833, 2837, 2843, 2851, 2857,
2861, 2879, 2887, 2897, 2903,
2909, 2917, 2927, 2939, 2953,
2957, 2963, 2969, 2971, 2999,
3001, 3011, 3019, 3023, 3037,
3041, 3049, 3061, 3067, 3079,
3083, 3089, 3109, 3119, 3121,
3137, 3163, 3167, 3169, 3181,
3187, 3191, 3203, 3209, 3217,
3221, 3229, 3251, 3253, 3257,
3259, 3271, 3299, 3301, 3307,
3313, 3319, 3323, 3329, 3331,
3343, 3347, 3359, 3361, 3371,
3373, 3389, 3391, 3407, 3413,
3433, 3449, 3457, 3461, 3463,
3467, 3469, 3491, 3499, 3511,
3517, 3527, 3529, 3533, 3539,
3541, 3547, 3557, 3559, 3571,
3581, 3583, 3593, 3607, 3613,
3617, 3623, 3631, 3637, 3643,
3659, 3671, 3673, 3677, 3691,
3697, 3701, 3709, 3719, 3727,
3733, 3739, 3761, 3767, 3769,
3779, 3793, 3797, 3803, 3821,
3823, 3833, 3847, 3851, 3853,
3863, 3877, 3881, 3889, 3907,
3911, 3917, 3919, 3923, 3929,
3931, 3943, 3947, 3967, 3989,
4001, 4003, 4007, 4013, 4019,
4021, 4027, 4049, 4051, 4057,
4073, 4079, 4091, 4093, 4099,
4111, 4127, 4129, 4133, 4139,
4153, 4157, 4159, 4177, 4201,
4211, 4217, 4219, 4229, 4231,
4241, 4243, 4253, 4259, 4261,
4271, 4273, 4283, 4289, 4297,
4327, 4337, 4339, 4349, 4357,
4363, 4373, 4391, 4397, 4409,
4421, 4423, 4441, 4447, 4451,
4457, 4463, 4481, 4483, 4493,
4507, 4513, 4517, 4519, 4523,
4547, 4549, 4561, 4567, 4583,
4591, 4597, 4603, 4621, 4637,
4639, 4643, 4649, 4651, 4657,
4663, 4673, 4679, 4691, 4703,
4721, 4723, 4729, 4733, 4751,
4759, 4783, 4787, 4789, 4793,
4799, 4801, 4813, 4817, 4831,
4861, 4871, 4877, 4889, 4903,
4909, 4919, 4931, 4933, 4937,
4943, 4951, 4957, 4967, 4969,
4973, 4987, 4993, 4999, 5003,
5009, 5011, 5021, 5023, 5039,
5051, 5059, 5077, 5081, 5087,
5099, 5101, 5107, 5113, 5119,
5147, 5153, 5167, 5171, 5179,
5189, 5197, 5209, 5227, 5231,
5233, 5237, 5261, 5273, 5279,
5281, 5297, 5303, 5309, 5323,
5333, 5347, 5351, 5381, 5387,
5393, 5399, 5407, 5413, 5417,
5419, 5431, 5437, 5441, 5443,
5449, 5471, 5477, 5479, 5483,
5501, 5503, 5507, 5519, 5521,
5527, 5531, 5557, 5563, 5569,
5573, 5581, 5591, 5623, 5639,
5641, 5647, 5651, 5653, 5657,
5659, 5669, 5683, 5689, 5693,
5701, 5711, 5717, 5737, 5741,
5743, 5749, 5779, 5783, 5791,
5801, 5807, 5813, 5821, 5827,
5839, 5843, 5849, 5851, 5857,
5861, 5867, 5869, 5879, 5881,
5897, 5903, 5923, 5927, 5939,
5953, 5981, 5987, 6007, 6011,
6029, 6037, 6043, 6047, 6053,
6067, 6073, 6079, 6089, 6091,
6101, 6113, 6121, 6131, 6133,
6143, 6151, 6163, 6173, 6197,
6199, 6203, 6211, 6217, 6221,
6229, 6247, 6257, 6263, 6269,
6271, 6277, 6287, 6299, 6301,
6311, 6317, 6323, 6329, 6337,
6343, 6353, 6359, 6361, 6367,
6373, 6379, 6389, 6397, 6421,
6427, 6449, 6451, 6469, 6473,
6481, 6491, 6521, 6529, 6547,
6551, 6553, 6563, 6569, 6571,
6577, 6581, 6599, 6607, 6619,
6637, 6653, 6659, 6661, 6673,
6679, 6689, 6691, 6701, 6703,
6709, 6719, 6733, 6737, 6761,
6763, 6779, 6781, 6791, 6793,
6803, 6823, 6827, 6829, 6833,
6841, 6857, 6863, 6869, 6871,
6883, 6899, 6907, 6911, 6917,
6947, 6949, 6959, 6961, 6967,
6971, 6977, 6983, 6991, 6997,
7001, 7013, 7019, 7027, 7039,
7043, 7057, 7069, 7079, 7103,
7109, 7121, 7127, 7129, 7151,
7159, 7177, 7187, 7193, 7207,
7211, 7213, 7219, 7229, 7237,
7243, 7247, 7253, 7283, 7297,
7307, 7309, 7321, 7331, 7333,
7349, 7351, 7369, 7393, 7411,
7417, 7433, 7451, 7457, 7459,
7477, 7481, 7487, 7489, 7499,
7507, 7517, 7523, 7529, 7537,
7541, 7547, 7549, 7559, 7561,
7573, 7577, 7583, 7589, 7591,
7603, 7607, 7621, 7639, 7643,
7649, 7669, 7673, 7681, 7687,
7691, 7699, 7703, 7717, 7723,
7727, 7741, 7753, 7757, 7759,
7789, 7793, 7817, 7823, 7829,
7841, 7853, 7867, 7873, 7877,
7879, 7883, 7901, 7907, 7919,
7927, 7933, 7937, 7949, 7951,
7963, 7993, 8009, 8011, 8017,
8039, 8053, 8059, 8069, 8081,
8087, 8089, 8093, 8101, 8111,
8117, 8123, 8147, 8161, 8167,
8171, 8179, 8191, 8209, 8219,
8221, 8231, 8233, 8237, 8243,
8263, 8269, 8273, 8287, 8291,
8293, 8297, 8311, 8317, 8329,
8353, 8363, 8369, 8377, 8387,
8389, 8419, 8423, 8429, 8431,
8443, 8447, 8461, 8467, 8501,
8513, 8521, 8527, 8537, 8539,
8543, 8563, 8573, 8581, 8597,
8599, 8609, 8623, 8627, 8629,
8641, 8647, 8663, 8669, 8677,
8681, 8689, 8693, 8699, 8707,
8713, 8719, 8731, 8737, 8741,
8747, 8753, 8761, 8779, 8783,
8803, 8807, 8819, 8821, 8831,
8837, 8839, 8849, 8861, 8863,
8867, 8887, 8893, 8923, 8929,
8933, 8941, 8951, 8963, 8969,
8971, 8999, 9001, 9007, 9011,
9013, 9029, 9041, 9043, 9049,
9059, 9067, 9091, 9103, 9109,
9127, 9133, 9137, 9151, 9157,
9161, 9173, 9181, 9187, 9199,
9203, 9209, 9221, 9227, 9239,
9241, 9257, 9277, 9281, 9283,
9293, 9311, 9319, 9323, 9337,
9341, 9343, 9349, 9371, 9377,
9391, 9397, 9403, 9413, 9419,
9421, 9431, 9433, 9437, 9439,
9461, 9463, 9467, 9473, 9479,
9491, 9497, 9511, 9521, 9533,
9539, 9547, 9551, 9587, 9601,
9613, 9619, 9623, 9629, 9631,
9643, 9649, 9661, 9677, 9679,
9689, 9697, 9719, 9721, 9733,
9739, 9743, 9749, 9767, 9769,
9781, 9787, 9791, 9803, 9811,
9817, 9829, 9833, 9839, 9851,
9857, 9859, 9871, 9883, 9887,
9901, 9907, 9923, 9929, 9931,
9941, 9949, 9967, 9973, 10007,
10009, 10037, 10039, 10061, 10067,
10069, 10079, 10091, 10093, 10099,
10103, 10111, 10133, 10139, 10141,
10151, 10159, 10163, 10169, 10177,
10181, 10193, 10211, 10223, 10243,
10247, 10253, 10259, 10267, 10271,
10273, 10289, 10301, 10303, 10313,
10321, 10331, 10333, 10337, 10343,
10357, 10369, 10391, 10399, 10427,
10429, 10433, 10453, 10457, 10459,
10463, 10477, 10487, 10499, 10501,
10513, 10529, 10531, 10559, 10567,
10589, 10597, 10601, 10607, 10613,
10627, 10631, 10639, 10651, 10657,
10663, 10667, 10687, 10691, 10709,
10711, 10723, 10729, 10733, 10739,
10753, 10771, 10781, 10789, 10799,
10831, 10837, 10847, 10853, 10859,
10861, 10867, 10883, 10889, 10891,
10903, 10909, 10937, 10939, 10949,
10957, 10973, 10979, 10987, 10993,
11003, 11027, 11047, 11057, 11059,
11069, 11071, 11083, 11087, 11093,
11113, 11117, 11119, 11131, 11149,
11159, 11161, 11171, 11173, 11177,
11197, 11213, 11239, 11243, 11251,
11257, 11261, 11273, 11279, 11287,
11299, 11311, 11317, 11321, 11329,
11351, 11353, 11369, 11383, 11393,
11399, 11411, 11423, 11437, 11443,
11447, 11467, 11471, 11483, 11489,
11491, 11497, 11503, 11519, 11527,
11549, 11551, 11579, 11587, 11593,
11597, 11617, 11621, 11633, 11657,
11677, 11681, 11689, 11699, 11701,
11717, 11719, 11731, 11743, 11777,
11779, 11783, 11789, 11801, 11807,
11813, 11821, 11827, 11831, 11833,
11839, 11863, 11867, 11887, 11897,
11903, 11909, 11923, 11927, 11933,
11939, 11941, 11953, 11959, 11969,
11971, 11981, 11987, 12007, 12011,
12037, 12041, 12043, 12049, 12071,
12073, 12097, 12101, 12107, 12109,
12113, 12119, 12143, 12149, 12157,
12161, 12163, 12197, 12203, 12211,
12227, 12239, 12241, 12251, 12253,
12263, 12269, 12277, 12281, 12289,
12301, 12323, 12329, 12343, 12347,
12373, 12377, 12379, 12391, 12401,
12409, 12413, 12421, 12433, 12437,
12451, 12457, 12473, 12479, 12487,
12491, 12497, 12503, 12511, 12517,
12527, 12539, 12541, 12547, 12553,
12569, 12577, 12583, 12589, 12601,
12611, 12613, 12619, 12637, 12641,
12647, 12653, 12659, 12671, 12689,
12697, 12703, 12713, 12721, 12739,
12743, 12757, 12763, 12781, 12791,
12799, 12809, 12821, 12823, 12829,
12841, 12853, 12889, 12893, 12899,
12907, 12911, 12917, 12919, 12923,
12941, 12953, 12959, 12967, 12973,
12979, 12983, 13001, 13003, 13007,
13009, 13033, 13037, 13043, 13049,
13063, 13093, 13099, 13103, 13109,
13121, 13127, 13147, 13151, 13159,
13163, 13171, 13177, 13183, 13187,
13217, 13219, 13229, 13241, 13249,
13259, 13267, 13291, 13297, 13309,
13313, 13327, 13331, 13337, 13339,
13367, 13381, 13397, 13399, 13411,
13417, 13421, 13441, 13451, 13457,
13463, 13469, 13477, 13487, 13499,
13513, 13523, 13537, 13553, 13567,
13577, 13591, 13597, 13613, 13619,
13627, 13633, 13649, 13669, 13679,
13681, 13687, 13691, 13693, 13697,
13709, 13711, 13721, 13723, 13729,
13751, 13757, 13759, 13763, 13781,
13789, 13799, 13807, 13829, 13831,
13841, 13859, 13873, 13877, 13879,
13883, 13901, 13903, 13907, 13913,
13921, 13931, 13933, 13963, 13967,
13997, 13999, 14009, 14011, 14029,
14033, 14051, 14057, 14071, 14081,
14083, 14087, 14107, 14143, 14149,
14153, 14159, 14173, 14177, 14197,
14207, 14221, 14243, 14249, 14251,
14281, 14293, 14303, 14321, 14323,
14327, 14341, 14347, 14369, 14387,
14389, 14401, 14407, 14411, 14419,
14423, 14431, 14437, 14447, 14449,
14461, 14479, 14489, 14503, 14519,
14533, 14537, 14543, 14549, 14551,
14557, 14561, 14563, 14591, 14593,
14621, 14627, 14629, 14633, 14639,
14653, 14657, 14669, 14683, 14699,
14713, 14717, 14723, 14731, 14737,
14741, 14747, 14753, 14759, 14767,
14771, 14779, 14783, 14797, 14813,
14821, 14827, 14831, 14843, 14851,
14867, 14869, 14879, 14887, 14891,
14897, 14923, 14929, 14939, 14947,
14951, 14957, 14969, 14983, 15013,
15017, 15031, 15053, 15061, 15073,
15077, 15083, 15091, 15101, 15107,
15121, 15131, 15137, 15139, 15149,
15161, 15173, 15187, 15193, 15199,
15217, 15227, 15233, 15241, 15259,
15263, 15269, 15271, 15277, 15287,
15289, 15299, 15307, 15313, 15319,
15329, 15331, 15349, 15359, 15361,
15373, 15377, 15383, 15391, 15401,
15413, 15427, 15439, 15443, 15451,
15461, 15467, 15473, 15493, 15497,
15511, 15527, 15541, 15551, 15559,
15569, 15581, 15583, 15601, 15607,
15619, 15629, 15641, 15643, 15647,
15649, 15661, 15667, 15671, 15679,
15683, 15727, 15731, 15733, 15737,
15739, 15749, 15761, 15767, 15773,
15787, 15791, 15797, 15803, 15809,
15817, 15823, 15859, 15877, 15881,
15887, 15889, 15901, 15907, 15913,
15919, 15923, 15937, 15959, 15971,
15973, 15991, 16001, 16007, 16033,
16057, 16061, 16063, 16067, 16069,
16073, 16087, 16091, 16097, 16103,
16111, 16127, 16139, 16141, 16183,
16187, 16189, 16193, 16217, 16223,
16229, 16231, 16249, 16253, 16267,
16273, 16301, 16319, 16333, 16339,
16349, 16361, 16363, 16369, 16381,
16411, 16417, 16421, 16427, 16433,
16447, 16451, 16453, 16477, 16481,
16487, 16493, 16519, 16529, 16547,
16553, 16561, 16567, 16573, 16603,
16607, 16619, 16631, 16633, 16649,
16651, 16657, 16661, 16673, 16691,
16693, 16699, 16703, 16729, 16741,
16747, 16759, 16763, 16787, 16811,
16823, 16829, 16831, 16843, 16871,
16879, 16883, 16889, 16901, 16903,
16921, 16927, 16931, 16937, 16943,
16963, 16979, 16981, 16987, 16993,
17011, 17021, 17027, 17029, 17033,
17041, 17047, 17053, 17077, 17093,
17099, 17107, 17117, 17123, 17137,
17159, 17167, 17183, 17189, 17191,
17203, 17207, 17209, 17231, 17239,
17257, 17291, 17293, 17299, 17317,
17321, 17327, 17333, 17341, 17351,
17359, 17377, 17383, 17387, 17389,
17393, 17401, 17417, 17419, 17431,
17443, 17449, 17467, 17471, 17477,
17483, 17489, 17491, 17497, 17509,
17519, 17539, 17551, 17569, 17573,
17579, 17581, 17597, 17599, 17609,
17623, 17627, 17657, 17659, 17669,
17681, 17683, 17707, 17713, 17729,
17737, 17747, 17749, 17761, 17783,
17789, 17791, 17807, 17827, 17837,
17839, 17851, 17863, 17881, 17891,
17903, 17909, 17911, 17921, 17923,
17929, 17939, 17957, 17959, 17971,
17977, 17981, 17987, 17989, 18013,
18041, 18043, 18047, 18049, 18059,
18061, 18077, 18089, 18097, 18119,
18121, 18127, 18131, 18133, 18143,
18149, 18169, 18181, 18191, 18199,
18211, 18217, 18223, 18229, 18233,
18251, 18253, 18257, 18269, 18287,
18289, 18301, 18307, 18311, 18313,
18329, 18341, 18353, 18367, 18371,
18379, 18397, 18401, 18413, 18427,
18433, 18439, 18443, 18451, 18457,
18461, 18481, 18493, 18503, 18517,
18521, 18523, 18539, 18541, 18553,
18583, 18587, 18593, 18617, 18637,
18661, 18671, 18679, 18691, 18701,
18713, 18719, 18731, 18743, 18749,
18757, 18773, 18787, 18793, 18797,
18803, 18839, 18859, 18869, 18899,
18911, 18913, 18917, 18919, 18947,
18959, 18973, 18979, 19001, 19009,
19013, 19031, 19037, 19051, 19069,
19073, 19079, 19081, 19087, 19121,
19139, 19141, 19157, 19163, 19181,
19183, 19207, 19211, 19213, 19219,
19231, 19237, 19249, 19259, 19267,
19273, 19289, 19301, 19309, 19319,
19333, 19373, 19379, 19381, 19387,
19391, 19403, 19417, 19421, 19423,
19427, 19429, 19433, 19441, 19447,
19457, 19463, 19469, 19471, 19477,
19483, 19489, 19501, 19507, 19531,
19541, 19543, 19553, 19559, 19571,
19577, 19583, 19597, 19603, 19609,
19661, 19681, 19687, 19697, 19699,
19709, 19717, 19727, 19739, 19751,
19753, 19759, 19763, 19777, 19793,
19801, 19813, 19819, 19841, 19843,
19853, 19861, 19867, 19889, 19891,
19913, 19919, 19927, 19937, 19949,
19961, 19963, 19973, 19979, 19991,
19993, 19997, 20011, 20021, 20023,
20029, 20047, 20051, 20063, 20071,
20089, 20101, 20107, 20113, 20117,
20123, 20129, 20143, 20147, 20149,
20161, 20173, 20177, 20183, 20201,
20219, 20231, 20233, 20249, 20261,
20269, 20287, 20297, 20323, 20327,
20333, 20341, 20347, 20353, 20357,
20359, 20369, 20389, 20393, 20399,
20407, 20411, 20431, 20441, 20443,
20477, 20479, 20483, 20507, 20509,
20521, 20533, 20543, 20549, 20551,
20563, 20593, 20599, 20611, 20627,
20639, 20641, 20663, 20681, 20693,
20707, 20717, 20719, 20731, 20743,
20747, 20749, 20753, 20759, 20771,
20773, 20789, 20807, 20809, 20849,
20857, 20873, 20879, 20887, 20897,
20899, 20903, 20921, 20929, 20939,
20947, 20959, 20963, 20981, 20983,
21001, 21011, 21013, 21017, 21019,
21023, 21031, 21059, 21061, 21067,
21089, 21101, 21107, 21121, 21139,
21143, 21149, 21157, 21163, 21169,
21179, 21187, 21191, 21193, 21211,
21221, 21227, 21247, 21269, 21277,
21283, 21313, 21317, 21319, 21323,
21341, 21347, 21377, 21379, 21383,
21391, 21397, 21401, 21407, 21419,
21433, 21467, 21481, 21487, 21491,
21493, 21499, 21503, 21517, 21521,
21523, 21529, 21557, 21559, 21563,
21569, 21577, 21587, 21589, 21599,
21601, 21611, 21613, 21617, 21647,
21649, 21661, 21673, 21683, 21701,
21713, 21727, 21737, 21739, 21751,
21757, 21767, 21773, 21787, 21799,
21803, 21817, 21821, 21839, 21841,
21851, 21859, 21863, 21871, 21881,
21893, 21911, 21929, 21937, 21943,
21961, 21977, 21991, 21997, 22003,
22013, 22027, 22031, 22037, 22039,
22051, 22063, 22067, 22073, 22079,
22091, 22093, 22109, 22111, 22123,
22129, 22133, 22147, 22153, 22157,
22159, 22171, 22189, 22193, 22229,
22247, 22259, 22271, 22273, 22277,
22279, 22283, 22291, 22303, 22307,
22343, 22349, 22367, 22369, 22381,
22391, 22397, 22409, 22433, 22441,
22447, 22453, 22469, 22481, 22483,
22501, 22511, 22531, 22541, 22543,
22549, 22567, 22571, 22573, 22613,
22619, 22621, 22637, 22639, 22643,
22651, 22669, 22679, 22691, 22697,
22699, 22709, 22717, 22721, 22727,
22739, 22741, 22751, 22769, 22777,
22783, 22787, 22807, 22811, 22817,
22853, 22859, 22861, 22871, 22877,
22901, 22907, 22921, 22937, 22943,
22961, 22963, 22973, 22993, 23003,
23011, 23017, 23021, 23027, 23029,
23039, 23041, 23053, 23057, 23059,
23063, 23071, 23081, 23087, 23099,
23117, 23131, 23143, 23159, 23167,
23173, 23189, 23197, 23201, 23203,
23209, 23227, 23251, 23269, 23279,
23291, 23293, 23297, 23311, 23321,
23327, 23333, 23339, 23357, 23369,
23371, 23399, 23417, 23431, 23447,
23459, 23473, 23497, 23509, 23531,
23537, 23539, 23549, 23557, 23561,
23563, 23567, 23581, 23593, 23599,
23603, 23609, 23623, 23627, 23629,
23633, 23663, 23669, 23671, 23677,
23687, 23689, 23719, 23741, 23743,
23747, 23753, 23761, 23767, 23773,
23789, 23801, 23813, 23819, 23827,
23831, 23833, 23857, 23869, 23873,
23879, 23887, 23893, 23899, 23909,
23911, 23917, 23929, 23957, 23971,
23977, 23981, 23993, 24001, 24007,
24019, 24023, 24029, 24043, 24049,
24061, 24071, 24077, 24083, 24091,
24097, 24103, 24107, 24109, 24113,
24121, 24133, 24137, 24151, 24169,
24179, 24181, 24197, 24203, 24223,
24229, 24239, 24247, 24251, 24281,
24317, 24329, 24337, 24359, 24371,
24373, 24379, 24391, 24407, 24413,
24419, 24421, 24439, 24443, 24469,
24473, 24481, 24499, 24509, 24517,
24527, 24533, 24547, 24551, 24571,
24593, 24611, 24623, 24631, 24659,
24671, 24677, 24683, 24691, 24697,
24709, 24733, 24749, 24763, 24767,
24781, 24793, 24799, 24809, 24821,
24841, 24847, 24851, 24859, 24877,
24889, 24907, 24917, 24919, 24923,
24943, 24953, 24967, 24971, 24977,
24979, 24989, 25013, 25031, 25033,
25037, 25057, 25073, 25087, 25097,
25111, 25117, 25121, 25127, 25147,
25153, 25163, 25169, 25171, 25183,
25189, 25219, 25229, 25237, 25243,
25247, 25253, 25261, 25301, 25303,
25307, 25309, 25321, 25339, 25343,
25349, 25357, 25367, 25373, 25391,
25409, 25411, 25423, 25439, 25447,
25453, 25457, 25463, 25469, 25471,
25523, 25537, 25541, 25561, 25577,
25579, 25583, 25589, 25601, 25603,
25609, 25621, 25633, 25639, 25643,
25657, 25667, 25673, 25679, 25693,
25703, 25717, 25733, 25741, 25747,
25759, 25763, 25771, 25793, 25799,
25801, 25819, 25841, 25847, 25849,
25867, 25873, 25889, 25903, 25913,
25919, 25931, 25933, 25939, 25943,
25951, 25969, 25981, 25997, 25999,
26003, 26017, 26021, 26029, 26041,
26053, 26083, 26099, 26107, 26111,
26113, 26119, 26141, 26153, 26161,
26171, 26177, 26183, 26189, 26203,
26209, 26227, 26237, 26249, 26251,
26261, 26263, 26267, 26293, 26297,
26309, 26317, 26321, 26339, 26347,
26357, 26371, 26387, 26393, 26399,
26407, 26417, 26423, 26431, 26437,
26449, 26459, 26479, 26489, 26497,
26501, 26513, 26539, 26557, 26561,
26573, 26591, 26597, 26627, 26633,
26641, 26647, 26669, 26681, 26683,
26687, 26693, 26699, 26701, 26711,
26713, 26717, 26723, 26729, 26731,
26737, 26759, 26777, 26783, 26801,
26813, 26821, 26833, 26839, 26849,
26861, 26863, 26879, 26881, 26891,
26893, 26903, 26921, 26927, 26947,
26951, 26953, 26959, 26981, 26987,
26993, 27011, 27017, 27031, 27043,
27059, 27061, 27067, 27073, 27077,
27091, 27103, 27107, 27109, 27127,
27143, 27179, 27191, 27197, 27211,
27239, 27241, 27253, 27259, 27271,
27277, 27281, 27283, 27299, 27329,
27337, 27361, 27367, 27397, 27407,
27409, 27427, 27431, 27437, 27449,
27457, 27479, 27481, 27487, 27509,
27527, 27529, 27539, 27541, 27551,
27581, 27583, 27611, 27617, 27631,
27647, 27653, 27673, 27689, 27691,
27697, 27701, 27733, 27737, 27739,
27743, 27749, 27751, 27763, 27767,
27773, 27779, 27791, 27793, 27799,
27803, 27809, 27817, 27823, 27827,
27847, 27851, 27883, 27893, 27901,
27917, 27919, 27941, 27943, 27947,
27953, 27961, 27967, 27983, 27997,
28001, 28019, 28027, 28031, 28051,
28057, 28069, 28081, 28087, 28097,
28099, 28109, 28111, 28123, 28151,
28163, 28181, 28183, 28201, 28211,
28219, 28229, 28277, 28279, 28283,
28289, 28297, 28307, 28309, 28319,
28349, 28351, 28387, 28393, 28403,
28409, 28411, 28429, 28433, 28439,
28447, 28463, 28477, 28493, 28499,
28513, 28517, 28537, 28541, 28547,
28549, 28559, 28571, 28573, 28579,
28591, 28597, 28603, 28607, 28619,
28621, 28627, 28631, 28643, 28649,
28657, 28661, 28663, 28669, 28687,
28697, 28703, 28711, 28723, 28729,
28751, 28753, 28759, 28771, 28789,
28793, 28807, 28813, 28817, 28837,
28843, 28859, 28867, 28871, 28879,
28901, 28909, 28921, 28927, 28933,
28949, 28961, 28979, 29009, 29017,
29021, 29023, 29027, 29033, 29059,
29063, 29077, 29101, 29123, 29129,
29131, 29137, 29147, 29153, 29167,
29173, 29179, 29191, 29201, 29207,
29209, 29221, 29231, 29243, 29251,
29269, 29287, 29297, 29303, 29311,
29327, 29333, 29339, 29347, 29363,
29383, 29387, 29389, 29399, 29401,
29411, 29423, 29429, 29437, 29443,
29453, 29473, 29483, 29501, 29527,
29531, 29537, 29567, 29569, 29573,
29581, 29587, 29599, 29611, 29629,
29633, 29641, 29663, 29669, 29671,
29683, 29717, 29723, 29741, 29753,
29759, 29761, 29789, 29803, 29819,
29833, 29837, 29851, 29863, 29867,
29873, 29879, 29881, 29917, 29921,
29927, 29947, 29959, 29983, 29989,
30011, 30013, 30029, 30047, 30059,
30071, 30089, 30091, 30097, 30103,
30109, 30113, 30119, 30133, 30137,
30139, 30161, 30169, 30181, 30187,
30197, 30203, 30211, 30223, 30241,
30253, 30259, 30269, 30271, 30293,
30307, 30313, 30319, 30323, 30341,
30347, 30367, 30389, 30391, 30403,
30427, 30431, 30449, 30467, 30469,
30491, 30493, 30497, 30509, 30517,
30529, 30539, 30553, 30557, 30559,
30577, 30593, 30631, 30637, 30643,
30649, 30661, 30671, 30677, 30689,
30697, 30703, 30707, 30713, 30727,
30757, 30763, 30773, 30781, 30803,
30809, 30817, 30829, 30839, 30841,
30851, 30853, 30859, 30869, 30871,
30881, 30893, 30911, 30931, 30937,
30941, 30949, 30971, 30977, 30983,
31013, 31019, 31033, 31039, 31051,
31063, 31069, 31079, 31081, 31091,
31121, 31123, 31139, 31147, 31151,
31153, 31159, 31177, 31181, 31183,
31189, 31193, 31219, 31223, 31231,
31237, 31247, 31249, 31253, 31259,
31267, 31271, 31277, 31307, 31319,
31321, 31327, 31333, 31337, 31357,
31379, 31387, 31391, 31393, 31397,
31469, 31477, 31481, 31489, 31511,
31513, 31517, 31531, 31541, 31543,
31547, 31567, 31573, 31583, 31601,
31607, 31627
};
int NumDivisors(long num) {
int factors[nprimes];
int i, nd=1, p, pn;
for (i=0; i<nprimes; i++) factors = 1;
pn = 0;
p = primes[0];
/* factor the number, keeping track of how many times
each prime can be divided into it */
while (p*p <= num) {
if (!(num % p)) {
do {
factors[pn]++;
num /= p;
} while (!(num % p));
} else {
p = primes[++pn];
}
}
if (num > 1) {
nd *= 2;
}
/* if the number is a^i * b^j * c^k * ...,
then it has (i+1)(j+1)(k+1)... divisors. */
for (i=0; i<=pn; i++) {
nd *= factors;
}
return nd;
}
int main() {
int i, n, nd, max_nd;
long lo, hi, best, count;
scanf("%d", &n);
for (i=0; i<n; i++) {
scanf("%ld %ld", &lo, &hi);
max_nd = 0;
for (count = lo; count<=hi; count++) {
nd = NumDivisors(count);
if (nd > max_nd) {
max_nd = nd;
best = count;
}
}
printf("Between %ld and %ld, %ld has a maximum of %d divisors.",
lo, hi, best, max_nd);
}
return 0;
}