#include <bits/stdc++.h>
using namespace std;
const int Inf = 0x3f3f3f3f;
int N;
double P;
int main() {
  scanf("%d%lf", &N, &P);
  int l = -1, r = N - 1;
  while (r - l > 1) {
    int m = (l + r) >> 1;
    double gal = (.5 * m * (N - m) * (N - m - 1) / 2 +
                  m * (m - 1) / 2 * (N - m) + m * (m - 1) * (m - 2) / 6) /
                 (N * (N - 1) * (N - 2) / 6);
    if (gal >= P - 1e-8)
      r = m;
    else
      l = m;
  }
  printf("%d\n", r);
  return 0;
}
