#include <bits/stdc++.h>
using namespace std;
const int NN = 111 * 1000;
int n, a, d;
int t[NN], v[NN];
int main() {
  ios::sync_with_stdio(false);
  cin >> n >> a >> d;
  for (int i = 0; i < n; i++) {
    cin >> t[i] >> v[i];
  }
  double Max = -1.;
  for (int i = 0; i < n; i++) {
    double v2 = (double)v[i] * v[i];
    double dx = v2 / a / 2.;
    dx = min((double)d, dx);
    double tl = sqrt(dx * 2. / a);
    double tr = (d - dx) / v[i];
    double t_cur = t[i] + tl + tr;
    Max = max(Max, t_cur);
    printf("%.16f\n", Max);
  }
}
