#include <bits/stdc++.h>
using namespace std;
int main() {
  int n;
  double a, d;
  scanf("%d%lf%lf", &n, &a, &d);
  double last_time = 0;
  for (int i = 0; i < n; i++) {
    double now_time = 0;
    double t, v;
    scanf("%lf%lf", &t, &v);
    if ((v * v) / (2.0 * a) >= d) {
      now_time = sqrt(2 * d / a);
    } else {
      now_time = v / a + (d - (1.0 * v * v) / (2.0 * a)) / v;
    }
    now_time += t * 1.0;
    if (now_time < last_time) now_time = last_time;
    last_time = now_time;
    printf("%.8lf", now_time);
    cout << '\n';
  }
  return 0;
}
