#include <bits/stdc++.h>
using namespace std;
double n, a, d, x, v;
double t, prevt;
int main() {
  cout.precision(10);
  cin >> n >> a >> d;
  for (int i = 0; i < n; ++i) {
    cin >> x >> v;
    double s = v * v / (2 * a);
    if (s >= d)
      t = x + sqrt(2 * d / a);
    else
      t = x + v / a + (d - s) / v;
    t = max(t, prevt);
    prevt = t;
    cout << fixed;
    cout << t << endl;
  }
  return 0;
}
