#include <bits/stdc++.h>
using namespace std;
void solve() {
  double n, a, d;
  cin >> n >> a >> d;
  double t, v, T[(long long)n];
  for (long long i = 0; i < n; i++) {
    cin >> t >> v;
    T[i] = t;
    double t1 = v / a;
    double s = (a * t1 * t1) / 2;
    if (s >= d) {
      T[i] += sqrt((2 * d) / a);
    } else {
      T[i] += t1 + (d - s) / v;
    }
    if (i) T[i] = max(T[i], T[i - 1]);
    cout << fixed << setprecision(10) << T[i] << '\n';
  }
}
signed main() {
  ios_base::sync_with_stdio(false);
  cin.tie(0);
  cout.tie(0);
  long long t = 1;
  while (t--) {
    solve();
  }
  return 0;
}
