#include <bits/stdc++.h>
using namespace std;
int n, a, d, t[100100], v[100100];
double ans[100100];
int main() {
  scanf("%d %d %d", &n, &a, &d);
  for (int i = 0; i < n; i++) scanf("%d %d", &t[i], &v[i]);
  for (int i = 0; i < n; i++) {
    double tt = v[i] * 1.0 / a;
    double dt = a * tt * tt / 2;
    if (d > dt)
      ans[i] = tt + (d - dt) / v[i];
    else
      ans[i] = sqrt(2.0 * d / a);
    ans[i] += t[i];
    if (i) ans[i] = max(ans[i], ans[i - 1]);
    printf("%.6lf\n", ans[i]);
  }
  return 0;
}
