#include<bits/stdc++.h>
using namespace std;
int main(){
	int n, l, r;
	int ans = 0;
	cin >> n >> l >> r;
	for(int i = l; i <= r; ++i){
		int tmp = 0;
		tmp = i%n;
		ans = max(ans, tmp);
	}
	cout << ans;
	return 0;
}

tle为甚么？