#include <bits/stdc++.h>
using namespace std;
int main() {
  int n, a, d;
  cin >> n >> a >> d;
  vector<int> t(n), v(n);
  for (int i = 0; i < n; i++) cin >> t[i] >> v[i];
  double lastTime = 0;
  for (int i = 0; i < n; i++) {
    double t0 = v[i] * 1. / a;
    double d0 = a * t0 * t0 / 2;
    if (d0 > d) {
      d0 = d;
      t0 = sqrt(2. * d0 / a);
    }
    t0 += (d - d0) / v[i];
    cout.precision(15);
    t0 += t[i];
    if (t0 < lastTime) t0 = lastTime;
    lastTime = t0;
    cout << t0 << endl;
  }
}
