#include <bits/stdc++.h>
using namespace std;
long long n, a, d;
long long t[100100], v[100100];
double maxt = 0;
int main() {
  cin >> n >> a >> d;
  for (int i = 0; i < n; i++) {
    cin >> t[i] >> v[i];
    double t1 = min(sqrt((double)2 * d / a), (double)v[i] / a);
    double s = a * t1 * t1 / 2;
    t1 += (d - s) / v[i];
    t1 += t[i];
    t1 = max(t1, maxt);
    maxt = max(t1, maxt);
    printf("%.10lf\n", t1);
  }
  return 0;
}
