Pollard_rho算法模板(大整数的因子分解)

终于懂了点Pollard_rho算法的原理

int pollard_rho(int n, int c)///c为自己设定的某值
{
	int x, y, d, i = 1, k = 2;
	x = rand() % (n - 1) + 1;
	y = x;
	while (true) {
		++i;
		x = (modular_multi(x, x, n) + c) % n;
		d = gcd(y - x, n);
		if (1 < d && d < n)
			return d;
		if (x == y)
			return n;
		if (i == k)
			y = x, k <<= 1;
	}
}

底下补个kuangbin牛分解质因数模板：http://www.cnblogs.com/kuangbin/archive/2012/08/19/2646396.html