求大佬解答

#include<bits/stdc++.h>
using namespace std;
unsigned long long int m,n,a[1000005];
int main(){
   	int m,n;
    cin>>m>>n;
    a[0] = a[1] = 1;
    for(int i = 2;i <= 10005;i++) a[i] = a[i - 1] + a[i - 2];
    cout<<a[n - m];
    return 0;
}