#include <bits/stdc++.h>
using namespace std;
int main() {
  double n, a, d;
  while (cin >> n >> a >> d) {
    pair<double, double> arr[int(n)];
    double mn = -1;
    for (int i = 0; i < n; i++) {
      scanf("%lf%lf", &arr[i].first, &arr[i].second);
      double dd = (arr[i].second * arr[i].second) / (2 * a);
      double time;
      if (d > dd) {
        time = arr[i].second / a + (d - dd) / arr[i].second;
      } else
        time = sqrt(2 * d / a);
      ;
      time += arr[i].first;
      if (time < mn)
        cout << setprecision(15) << mn << "\n";
      else
        cout << setprecision(15) << time << "\n";
      if (time < mn)
        mn = mn;
      else
        mn = time;
    }
  }
  return 0;
}
