Codevs 3285 Circle Game

This is the first question of NOIP2013. The end of the first thing you did without reading the question was heavy.

Simplified version Test Instructions: (x+10^k*m)%n.

Fast power chaos.

#include <iostream>
#include <cstdio>
using namespace Std;
Long Long n,m,k,x;
void work ()
{
Long Long R=10%n,ans=1;
while (k!=0)
{
if (k&1)
ans=ans*r%n;
r=r*r%n;
k=k>>1;
}
ans=ans*m%n;
x= (X+ans)%n;
}
int main ()
{
scanf ("%lld%lld%lld%lld", &n,&m,&k,&x);
Work ();
printf ("%lld", X);
return 0;
}

Codevs 3285 Circle Game