#include <cstdio>
#include <iostream>
#include <algorithm>

using namespace std;

int main()
{
    int n, l, r;
    cin >> n >> l >> r;
    if((l / n + 1) * n <= r || (l % n == 0 && (l / n) + n <= r))
    {
        cout << n - 1 << endl;
        return 0;
    }
    cout << r % n << endl;
    return 0;
}

最后一个点WA