#include <bits/stdc++.h>
using namespace std;
int n;
double a, b;
int main() {
  while (scanf("%d%lf%lf", &n, &a, &b) == 3) {
    int i;
    double last = 0;
    for (i = 0; i < n; i++) {
      double t, v;
      scanf("%lf%lf", &t, &v);
      double len = v * v / 2.0 / a;
      double tmp;
      if (len >= b) {
        tmp = sqrt(2.0 * b / a);
        v = sqrt(b * 2.0 * a);
      } else
        tmp = v / a + (b - len) / v;
      if (tmp + t > last) last = tmp + t;
      printf("%.8f\n", last);
    }
  }
  return 0;
}
