Luogu: P3197 [HNOI2008] Jailbreak (popularization/improvement -, fast power, divide and conquer)

topic:

Analysis: Is the brain power really bad? I can't do such a short answer math problem.

All possible-nothing adjacent is the result.

The problem is transformed into a quick power. . .

#include<bits/stdc++.h>
using namespace std;
long long f(long long a,long long b,int c)
{
    
    //a 的 b次方  取余c 
 if(b==0) return 1;
 long long ans=f(a,b/2,c);
 ans=ans*ans%100003;
 if(b%2==1) ans=ans*a%100003;
 return ans;
}
int main()
{
    
    
 long long m,n;
 cin>>m>>n;
 long long ans=(f(m,n,100003)-m*f(m-1,n-1,100003)%100003+100003)%100003;
 cout<<ans;
}