#include <bits/stdc++.h>
using namespace std;
int32_t main() {
  ios::sync_with_stdio(0);
  cin.tie(0);
  cout.tie(0);
  ;
  double n, a, d, t, v;
  cin >> n >> a >> d;
  double prevTime = 0.0;
  for (long long i = 0; i < n; i++) {
    cin >> t >> v;
    double s = (v * v) / (2.0 * a);
    double time;
    if (s > d) {
      time = sqrt(2.0 * d / a);
    } else {
      time = (v / a) + (d - s) / v;
    }
    prevTime = max(t + time, prevTime);
    printf("%.6lf\n", prevTime);
  }
  return 0;
}
