MillarRabin模版 随机测大素数

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支持long long

#include <algorithm>
typedef long long ll;
ll GCD(ll a, ll b) { return b ? GCD(b, a % b) : a; }
ll MultiMod(ll a, ll b, ll n) { // a * b % n
	ll res = 0; MillarRabin
	a %= n;
	while (b > 0) {
		if (b & 1) {
			res += a;
			if (res >= n) res -= n;
		}
		a <<= 1;
		if (a >= n) a -= n;
		b >>= 1;
	}
	return res;
}
ll QuickMod(ll a, ll b, ll n) { // a ^ b % n
	ll res = 1;
	a %= n;
	while (b > 0) {
		if (b & 1) res = MultiMod(res, a, n);
		a = MultiMod(a, a, n); b >>= 1;
	}
	return res;
}
bool MillarRabin(ll n) { // 判断是否素数
	if (n == 2 || n == 3 || n == 5 || n == 7 || n == 11) return true;
	if (n == 1 || !(n & 1) || !(n % 3) || !(n % 5) || !(n % 7) || !(n % 11)) return false;
	ll t = 0, m = n - 1, x, y;
	while (!(m & 1)) { m >>= 1; t++; }
	for (int i = 0; i < 10; i++) {
		ll a = rand() % (n - 2) + 2;
		x = QuickMod(a, m, n);
		for (ll j = 0; j < t; j++) {
			y = MultiMod(x, x, n);
			if (y == 1 && x != 1 && x != n - 1) return false;
			x = y;
		}
		if (y != 1) return false;
	}
	return true;
}

MillarRabin模版 随机测大素数

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原文地址：http://blog.csdn.net/qq574857122/article/details/44872845