题解

#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
ll n, l, r;
ll ans;
int main(){
    cin >> n >> l >> r;
    for(ll i = l; i <= r; i++){
        ll ch_cdy = i / n;
        ll own = i - (i / n) * n;
        ans = max(ans, own);
    }
    cout << ans;
    return 0;
}