#include <bits/stdc++.h>
using namespace std;
inline bool equal(double _x, double _y) {
  return _x > _y - 1e-9 && _x < _y + 1e-9;
}
double ans[100005];
int main() {
  int n;
  double a, d, v, t;
  scanf("%d%lf%lf", &n, &a, &d);
  ans[0] = .0;
  for (int i = 1; i <= n; i++) {
    scanf("%lf%lf", &t, &v);
    if (d <= v * v / 2 / a)
      ans[i] = sqrt(2 * d / a) + t;
    else
      ans[i] = d / v + v / 2 / a + t;
    ans[i] = max(ans[i - 1], ans[i]);
    printf("%.5lf\n", ans[i]);
  }
}
