#include <bits/stdc++.h>
using namespace std;
double t[100001], v[100001], fin[100001];
int main() {
  double n, a, d;
  cin >> n >> a >> d;
  for (int i = 0; i < n; ++i) {
    cin >> t[i] >> v[i];
  }
  cout.precision(5);
  for (int i = 0; i < n; ++i) {
    fin[i] = 2 * d * a <= v[i] * v[i] ? sqrt(2.0 * d / a)
                                      : (d / v[i] + v[i] / (2 * a));
    fin[i] += t[i];
    if (i) fin[i] = max(fin[i], fin[i - 1]);
    cout << fixed << fin[i] << endl;
  }
  return 0;
}
