#include <bits/stdc++.h>
using namespace std;
int t[200000];
int v[200000];
double ans[200000];
int main() {
  int n, a, d;
  cin >> n >> a >> d;
  for (int(i) = (0); (i) < (n); ++(i)) cin >> t[i] >> v[i];
  for (int(i) = (0); (i) < (n); ++(i)) {
    double t1 = (v[i] + 0.0) / (a + 0.0);
    double t2 = (d - a * t1 * t1 * 0.5) / (v[i] + 0.0);
    if (a * t1 * t1 * 0.5 >= d) {
      t1 = sqrt(2.0 * d / (a + 0.0));
      t2 = 0;
    }
    double tt = t1 + t2;
    if (i == 0)
      ans[i] = t[i] + tt;
    else {
      double l = t[i], r = t[i] + tt;
      if (r > ans[i - 1])
        ans[i] = r;
      else
        ans[i] = ans[i - 1];
    }
  }
  for (int(i) = (0); (i) < (n); ++(i)) printf("%.6f\n", ans[i]);
  return 0;
}
