#include using namespace std;

int f(int n, int m) { int a=0; for(int i=2;i<=n;++i) a = (a + m) % i; return a + 1; } int n,m; int main() { cin>>n>>m; cout<<f(n, m)<< endl; return 0; }

# include <bits/stdc++.h>

using namespace std;
const int N=1e7+5;
int n,m,cnt,f[N];
int main(){
	cin>>n>>m;
	for(int i = 2;i<=n;i++)
		f[i]=(f[i-1]+m)%i;
	cout<<f[n]+1;
	return 0;
}

数学解法

#include <iostream>
using namespace std;
 
int f(int n, int m) {
    int a=0;
    for(int i=2;i<=n;++i) a = (a + m) % i;
    return a + 1;
}
int n,m;
int main() {
    cin>>n>>m;
    cout<<f(n, m)<< endl;
    return 0;
}