#include <iostream>
#include <stdio.h>
#include <math.h>
#include <cmath>
using namespace std;

int main()
{
    int N,S,K;
    cin >> N >> S;
    K = N * (N - 1) / 2;
    if(fabs(S) > N * (N - 1) / 2) {
        cout << "0\n";
        return 0;
    }
}