题解 | #快速乘#

#include <iostream>
#include<algorithm>
using namespace std;
typedef long long LL;
int qmul(int a, int b, int p){
    LL res = 0;
    while(b){
        if(b & 1) res = (LL)(res + a) % p;
        b >>= 1;
        a = (a + a) % p;
    }
    return res;
}

int main() {
    int q;
    cin >> q;
    while(q --){
        int a, b, p;
        cin >> a >> b >> p;
        cout << qmul(a, b, p) << endl;
    }
    return 0;    
}