#include <bits/stdc++.h>
using namespace std;
using lint = long long;
template<class T = int> using V = vector<T>;
template<class T = int> using VV = V< V<T> >;

int main() {
  cin.tie(nullptr); ios::sync_with_stdio(false);
  lint h, w; cin >> h >> w;
  w = abs(w);
  if (!h or !w) return cout << 0 << '\n', 0;
  lint q = w / h, r = w - q * h;
  lint res = q * (h * (h + 1) / 2) + (r ? h + r * (r - 1) / 2 : 0);
  cout << res << '\n';
}