【Codevs 2115】数集分割

http://codevs.cn/problem/2115/

 // <2115.cpp> - Sun Oct  9 12:58:23 2016
 // This file is made by YJinpeng，created by XuYike's black technology automatically.
 // Copyright (C) 2016 ChangJun High School, Inc.
 // I don't know what this program is.

 #include <iostream>
 #include <cstdio>
 #define LL long long
 using namespace std;
 int quick_pow(int a,int b,int p){
     int w=;
     while(b){
         if(b&)w=(w*a)%p;
         b>>=;a=(a*a)%p;
     }
     return w;
 }
 int main()
 {
     freopen("2115.in","r",stdin);
     freopen("2115.out","w",stdout);
     int n;scanf("%d",&n);
     int ans=(quick_pow(,n/,)-)*(quick_pow(,(n-)/,)-);
     ans%=;printf((n>=?"%.4d":"%d"),ans);
     return ;
 }