#include <bits/stdc++.h>
using namespace std;
double ans[1000099];
int main() {
  double n, a, d;
  while (scanf("%lf%lf%lf", &n, &a, &d) != EOF) {
    double t, v;
    for (int i = 0; i < n; i++) {
      scanf("%lf%lf", &t, &v);
      double now = v / a;
      if (0.5 * a * now * now < d) {
        ans[i] = now + (d - 0.5 * a * now * now) / v + t;
      } else {
        ans[i] = sqrt(2.0 * d / a) + t;
      }
    }
    double now = ans[0];
    for (int i = 0; i < n; i++) {
      if (ans[i] < now)
        cout << now << endl;
      else {
        cout << ans[i] << endl;
        now = ans[i];
      }
    }
  }
}
