#include <bits/stdc++.h>
using namespace std;
int main() {
  ios_base::sync_with_stdio(0);
  cin.tie(0);
  cout.tie(0);
  long long n;
  double a, d;
  cin >> n >> a >> d;
  double prev = -1;
  while (n--) {
    double t, v, time;
    cin >> t >> v;
    double s = v * v / (2 * a);
    if (s > d)
      time = sqrt(2 * d / a);
    else
      time = d / v + v / (2 * a);
    if (time + t > prev)
      printf("%.10lf \n", time + t), prev = time + t;
    else
      printf("%.10lf \n", prev);
  }
  return 0;
}
