praksa

Od vpisanega števila v zanki odštevaj 1 in hkrati preverjaj, če pri deljenju vpisanega števila s tem številom dobiš ostanek ali ne. Čim ne dobiš ostanka, število ni praštevilo (razen če si pri odštevanju že prišel do 1, potem je). Bolj optimizirana varianta pa je, da uporabiš nad vpisanim številom funkcijo sqrt, in nato odštevaš 1 od tega števila do 1.

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
Press any key to continue . . . :D