#include <bits/stdc++.h>
using namespace std;
const int DBG = 0, INF = int(1e9);
string toString(long long k) {
  stringstream ss;
  ss << k;
  string res;
  ss >> res;
  return res;
}
int toInt(string s) {
  stringstream ss;
  ss << s;
  int res;
  ss >> res;
  return res;
}
int main() {
  ios_base::sync_with_stdio(0);
  cout.setf(ios::fixed);
  cout << setprecision(10);
  int n, a, d;
  cin >> n >> a >> d;
  vector<pair<int, int> > V(n);
  for (int _n = (n), i = 0; i < _n; ++i) cin >> V[i].first >> V[i].second;
  double prev = -1;
  for (int _n = (n), i = 0; i < _n; ++i) {
    double accTime = double(V[i].second) / double(a);
    double accDst = double(V[i].second) * accTime * 0.5;
    if (accDst >= d) {
      double t = sqrt((2. * double(d)) / double(a));
      prev = max(t + double(V[i].first), prev);
    } else {
      double remDst = d - accDst;
      double remTime = remDst / double(V[i].second);
      prev = max(accTime + remTime + double(V[i].first), prev);
    }
    cout << prev << endl;
  }
  return 0;
}
