B - A/B HDU - 快速幂-逆元

#include<iostream>
#include<cmath>
#include<bits/stdc++.h>
using namespace std;
#define ll long long
ll qpow(ll x,ll n,ll mod)
{
    ll res=1;
    while(n>0)
    {
        if(n%2==1)
        {
            res*=x;
            res%=mod;
        }
        x*=x;
        x%=mod;
        n/=2;
    }
    return res;
}
int main()
{
    ll n,mod=9973,m;
    int t;
    cin>>t;
    while(t--)
    {
        cin>>m>>n;
        cout<<qpow(n,mod-2,mod)*m%mod<<endl;
    }
    return 0;
}