UVa:11029 Leading and Trailing

#include<iostream>
#include<cstdio>
#include<cstring>
#include<cstdlib>
#include<cmath>
#include<algorithm>
using namespace std;
double Convers(double val)
{
    while(val>=1000)
        val=val/10;
    return val;
}
void quickpow(double a,int b,int k,double &fro,int &rear)
{
    fro=1.0;
    rear=1;
    while(k)
    {
        if(k&1)
        {
            fro*=a;
            fro=Convers(fro);
            rear=rear*b%1000;
        }
        a*=a;
        a=Convers(a);
        b=b*b%1000;
        k=k>>1;
    }
}
int main()
{
    int T;
    scanf("%d",&T);
    while(T--)
    {
        int n,k;
        scanf("%d%d",&n,&k);
        double v;
        int u;
        quickpow(Convers(n),n%1000,k,v,u);
        printf("%d...%03d\n",(int)v,u%1000);
    }
    return 0;
}