#include <bits/stdc++.h>
using namespace std;
int main() {
  double n, a, d, t, v;
  cin >> n >> a >> d;
  double minitime = 0;
  for (int i = 0; i < n; i++) {
    cin >> t >> v;
    double t1 = v / a;
    double s = a * 0.5 * t1 * t1;
    if (s > d) {
      t += sqrt(2 * d / a);
    } else {
      double x = d - s;
      double t2 = x / v;
      t += t1 + t2;
    }
    t = max(minitime, t);
    minitime = t;
    cout << t << endl;
  }
  return 0;
}
