快速冪模板

#include <iostream>
using namespace std;
int main() {
	int a, b, p;
	cin >> a >> b >> p;
	int ans = 1 % p;
	while (b) {
		if (b & 1)
			ans = (ans * a) % p;
		a = (a * a) % p;
		b = b >> 1;
	}
	cout << ans;
	return 0;
}