#include <bits/stdc++.h>
using namespace std;
double a, d;
int n;
int main() {
  cin >> n >> a >> d;
  vector<double> ans(n);
  for (int i = 0; i < n; ++i) {
    double t, v;
    scanf("%lf%lf", &t, &v);
    double p = v / a;
    double done = v / 2 * p;
    if (done >= d) {
      ans[i] = t + sqrt(d * 2 / a);
    } else {
      ans[i] = t + p + (d - done) / v;
    }
  }
  for (int i = 1; i < n; ++i) {
    ans[i] = max(ans[i], ans[i - 1]);
  }
  for (int i = 0; i < n; ++i) {
    printf("%0.10lf\n", ans[i]);
  }
  return 0;
}
