#include <bits/stdc++.h>
int main(void) {
  int n;
  double a, d;
  scanf("%d%lf%lf", &n, &a, &d);
  double t[100100], v[100100], ans[100100], min = 0;
  int i, j;
  for (i = 0; i < n; i++) {
    scanf("%lf%lf", &t[i], &v[i]);
    if (v[i] * v[i] / (2 * a) > d)
      ans[i] = t[i] + sqrt(2 * d / a);
    else
      ans[i] = t[i] + (d / v[i]) + (v[i] / (2 * a));
    if (ans[i] < min)
      ans[i] = min;
    else
      min = ans[i];
  }
  for (i = 0; i < n; i++) {
    printf("%.5lf\n", ans[i]);
  }
  return 0;
}
