#include <bits/stdc++.h>
using namespace std;
double a, d, v, t, last;
int n, i;
int main() {
  scanf("%d%lf%lf", &n, &a, &d);
  last = 0;
  for (i = 1; i <= n; i++) {
    scanf("%lf%lf", &t, &v);
    double tt = (v * 1.) / (a * 1.) + t;
    double s = v * 1. * v * 1. / (2. * a * 1.);
    if (s <= d)
      tt += ((d - s) / v * 1.);
    else
      tt = sqrt((2. * d / (a * 1.))) + t;
    if (tt < last) tt = last;
    printf("%lf\n", tt);
    last = tt;
  }
}
