#include <bits/stdc++.h>
using namespace std;
int main() {
  double now = 0.0, a, d, v, t;
  int i, n, ti, vi;
  cin >> n >> a >> d;
  for (i = 0; i < n; i++) {
    scanf("%d", &ti);
    scanf("%d", &vi);
    t = 0.0 + ti;
    v = 0.0 + vi;
    if (d > v * v * 0.5 / a)
      now = max(now, d / v + v * 0.5 / a + t);
    else
      now = max(now, sqrt(2.0 * d / a) + t);
    printf("%.12f\n", now);
  }
  return 0;
}
