#include <bits/stdc++.h>
using namespace std;
long long n, a, d;
long long t[100002];
long long v[100002];
int main() {
  cout << setprecision(9);
  cin >> n >> a >> d;
  for (int i = 0; i < n; i++) cin >> t[i] >> v[i];
  double prev = 0;
  for (int i = 0; i < n; i++) {
    double tim = 0;
    if ((v[i]) * (v[i]) > 2 * d * a)
      tim = sqrt(2.0 * d / a);
    else
      tim = (d * 1.0 - (v[i] * v[i]) / 2.0 / a) / v[i] + v[i] * 1.0 / a;
    if (t[i] + tim < prev) {
      cout << prev << endl;
    } else {
      cout << t[i] + tim << endl;
      prev = t[i] + tim;
    }
  }
  return 0;
}
