POJ-1995-Raising Modulo Numbers

#include<cstdio>
#include<cstring>
#include<iostream>
using namespace std;
const int maxn=50000;
int m,h;
long long ans;
long long QMulti(long long a,long long n)
{
long long ans=1;
while(n)
{
if(n&1)
ans=(ans*a)%m;
a=(a*a)%m;
n>>=1;
}
return ans;
}
int main()
{
int T;
scanf("%d",&T);
while(T--)
{
ans=0;
scanf("%d%d",&m,&h);
for(int i=0;i<h;i++)
{
long long a,b;
scanf("%I64d%I64d",&a,&b);
ans=(ans+QMulti(a,b))%m;
}
printf("%I64d\n",ans);
}
return 0;
}