#include <bits/stdc++.h>
const double eps = 1e-9;
const int oo = 1000000000;
const double E = 2.7182818284590452353602874713527;
const double pi = 3.1415926535897932384626433832795;
using namespace std;
int main() {
  int n, a, d;
  double ans = 0;
  cin >> n >> a >> d;
  while (n--) {
    int t, v;
    double t2, s;
    scanf("%d%d", &t, &v);
    t2 = 1. * v / a;
    if (t2 * t2 * a / 2 <= d)
      s = t2 + (d - t2 * t2 * a / 2) / v;
    else
      s = sqrt(2. * d / a);
    ans = max(ans, s + t);
    printf("%lf\n", ans);
  }
  return 0;
}
