#include <bits/stdc++.h>
using namespace std;
double t[100010], v[100010];
int n;
double a, d;
double ans[100010];
int main() {
  scanf("%d%lf%lf", &n, &a, &d);
  for (int i = 0; i < n; i++) {
    scanf("%lf%lf", &t[i], &v[i]);
  }
  for (int i = 0; i < n; i++) {
    if (2 * a * d > v[i] * v[i])
      ans[i] = t[i] + v[i] / a + (d - v[i] * v[i] / a / 2) / v[i];
    else {
      ans[i] = sqrt(2 * a * d) / a + t[i];
    }
    ans[i] = max(ans[i], ans[i - 1]);
    printf("%.5lf\n", ans[i]);
  }
}
