#include <bits/stdc++.h>
using namespace std;
int n;
double a, len;
int main() {
  scanf("%d%lf%lf", &n, &a, &len);
  double last = 0;
  for (int i = 0; i < n; i++) {
    double t, s_lim;
    scanf("%lf%lf", &t, &s_lim);
    double st_t = s_lim / a;
    double st_l = s_lim * st_t / 2;
    if (st_l < len)
      t += st_t + (len - st_l) / s_lim;
    else
      t += sqrt(len * 2 / a);
    t = max(t, last);
    printf("%.10lf\n", t);
    last = t;
  }
  return 0;
}
