#include <bits/stdc++.h>
using namespace std;
void Yahia74() {
  ios::sync_with_stdio(false), cin.tie(nullptr), cout.tie(nullptr);
}
const int N = 2e5 + 74, OO = 0x3f3f3f3f, MOD = (int)1e9 + 7;
int main() {
  Yahia74();
  long long n, a, d, t, v;
  cin >> n >> a >> d;
  double mx = -OO;
  for (int i = 0; i < n; i++) {
    cin >> t >> v;
    if ((v * v / (2.0 * a)) > d)
      mx = max(mx, 1.0 * t + sqrt((2.0 * d) / a));
    else
      mx = max(mx, t + (v * v + 2.0 * a * d) / (2.0 * a * v));
    cout << setprecision(6) << fixed << mx << '\n';
  }
  return 0;
}
