C++-POJ1995-Raising Modulo Numbers[快速幂]

#include <cstdio>
typedef long long ll;
int quick_pow(ll a,ll b,ll mod){
    ll ans=1;
    for(;b;a=(a*a)%mod,b>>=1)if(b&1)ans=(ans*a)%mod;
    return ans;
}
int main(){
    int z,m,h,a,b,ans;
    for(scanf("%d",&z);z--;){
        scanf("%d%d",&m,&h),ans=0;
        while(h--)scanf("%d%d",&a,&b),ans=(ans+quick_pow(a,b,m))%m;
        printf("%d\n",ans);
    }
    return 0;
}