#include <bits/stdc++.h>
using namespace std;
int main() {
  int n;
  double a, d;
  cin >> n >> a >> d;
  double t, v, buf;
  double time = 0, now;
  for (int i = 0; i < n; i++) {
    cin >> t >> v;
    buf = v * v / (2 * a);
    if (buf > d) {
      now = t + sqrt(d * 2.0 / a);
    } else {
      now = t + v / a + (d - buf) / v;
    }
    time = ((time) < (now) ? (now) : (time));
    cout << time << endl;
  }
  return 0;
}
