UVa 10006 Carmichael Numbers

/*File: 10006.cppAuthor: ACboyDate: 2010-4-22Result: ACDescripition: UVa 10006 Carmichael Numbers*/#include <iostream>using namespace std;int vis[70000];// 快速幂取模(a^b % n)unsigned long ExpModula(unsigned long a, unsigned long b, unsigned long n) {unsigned long m = 1;while (b) {if (b & 1) {m = ((a % n) * (m % n)) % n;}b >>= 1;a = ((a % n) * (a % n)) % n;}return m;}// 素数刷法vis[i] == 0则表示i是素数，vis[i] == 1则表示i是合数。void select_prime() {memset(vis, 0, sizeof(vis));int i, j;for (i = 2; i <= 65000; i++) {if (!vis[i]) {for (j = i * 2; j <= 65000; j += i) {vis[j] = 1;}}}}int prime(int a) {int ok = 1;for (int i = 2; i * i <= a; i++) {if (a % i == 0) {ok = 0;break;}}return ok;}int main() {unsigned long n;#ifndef ONLINE_JUDGEfreopen("10006.txt", "r", stdin);#endifselect_prime();while (cin >> n) {if (n == 0) break;if (!vis[n]) {printf("%d is normal./n", n);continue;}int ok = 1;for (unsigned long i = 2; i < n; i++) {if (ExpModula(i, n, n) != i) {ok = 0;break;}}if (ok) {printf("The number %d is a Carmichael number./n", n);} else {printf("%d is normal./n", n);}}return 0;}