#include <bits/stdc++.h>
using namespace std;
double ans[100100];
int n;
double a, d;
int main() {
  scanf("%d%lf%lf", &n, &a, &d);
  double tmp = sqrt(d * 2 / a);
  for (int i = 1; i <= n; i++) {
    double x, y;
    scanf("%lf%lf", &x, &y);
    double cur = y * y / a / 2;
    if (cur >= d)
      ans[i] = x + tmp;
    else
      ans[i] = x + y / a + (d - cur) / y;
  }
  for (int i = 1; i <= n; i++) {
    ans[i] = max(ans[i], ans[i - 1]);
    printf("%.6lf\n", ans[i]);
  }
  return 0;
}
