#include <bits/stdc++.h>
using namespace std;
int n;
long double a, d, t, v;
long double acctime, accdist, consdist, cur, best;
int main() {
  cin >> n >> a >> d;
  for (int i = 0; i < n; i++) {
    cin >> t >> v;
    acctime = v / a;
    accdist = a * acctime * acctime / 2;
    if (accdist <= d) {
      consdist = d - accdist;
      cur = acctime + consdist / v;
    } else {
      cur = sqrt(2 * d / a);
    }
    best = max(best, cur + t);
    cout << setprecision(12) << best << endl;
  }
  return 0;
}
