T1：幸运儿
幸运儿是 \((x-1+m-1)\%n+1\)
代码实现
#include <bits/stdc++.h>
#define rep(i, n) for (int i = 0; i < (n); ++i)
using namespace std;
int main() {
int n, x, m;
cin >> n >> x >> m;
--x;
int ans = (x+m-1)%n+1;
cout << ans << '\n';
return 0;
}