#include <bits/stdc++.h>
using namespace std;
int cmp(double a, double b) {
  if (fabs(a - b) < 1e-8) return 0;
  if (a < b) return -1;
  return 1;
}
int main() {
  int n;
  double a, d;
  scanf("%d%lf%lf", &n, &a, &d);
  double res = 0;
  for (int i = 0; i < n; i++) {
    double t0, v;
    scanf("%lf %lf", &t0, &v);
    double ta = v / a, rt;
    if (cmp(ta * ta * a / 2.0, d) >= 0)
      rt = sqrt(2 * d / a);
    else {
      double pd = ta * ta * a / 2.0;
      rt = ta + (d - pd) / v;
    }
    res = max(res, t0 + rt);
    printf("%.6lf\n", res);
  }
  return 0;
}
