#include <bits/stdc++.h>
using namespace std;
int main() {
  ios_base::sync_with_stdio(false);
  int N;
  double A, D;
  cin >> N >> A >> D;
  double prev = 0.0;
  cout << fixed;
  cout.precision(9);
  for (int i = 1; i <= N; i++) {
    double t, v;
    cin >> t;
    cin >> v;
    double t_stop = sqrt(2.0 * D / A);
    double t_max = v / A;
    double t_ans = t;
    if (t_stop < t_max)
      t_ans += t_stop;
    else
      t_ans += t_max + D / v - v / (2.0 * A);
    t_ans = max(prev, t_ans);
    cout << t_ans << endl;
    prev = t_ans;
  }
  return 0;
}
