【poj1995】Raising Modulo Numbers

#include<stdio.h>
__int64 quickpow(int m,int n,int s) {
    __int64 ans=1,base=m;
    while(n) {
        if(n&1) {
            ans=ans*base%s;
        }
        base=base*base%s;
        n>>=1;
    }
    return ans;
}
int main() {
    int T;
    scanf("%d",&T);
    while(T--) {
        int k,n,x,y;
        __int64 sum=0;
        scanf("%d %d",&k,&n);
        for(int l=0; l<n; l++) {
            scanf("%d %d",&x,&y);
            sum=(sum+quickpow(x,y,k))%k;
        }
        printf("%I64d\n",sum);
    }
    return 0;
}