#include <bits/stdc++.h>
using namespace std;
int main() {
  int n;
  double a, d;
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  scanf("%d %lf %lf", &n, &a, &d);
  double t, v;
  double inis, init, rems, last, total;
  double mini = -10000000000.0;
  for (int i = 0; i < n; i++) {
    scanf("%lf %lf", &t, &v);
    init = (v) / a;
    inis = (v) * (v) / (2 * a);
    if (inis >= d) {
      rems = sqrt(d * 2 * a);
      total = rems / a;
      total += t;
    } else {
      rems = d - inis;
      last = rems / v;
      total = last + t + init;
    }
    if (total > mini) {
      mini = total;
    }
    printf("%.6lf\n", mini);
  }
}
