#include <bits/stdc++.h>
using namespace std;
int n;
double a, d;
double v[100010];
double t[100010];
double ans[100010];
int main() {
  cin >> n >> a >> d;
  int i;
  for (i = 0; i < n; i++) cin >> t[i] >> v[i];
  for (i = 0; i < n; i++) {
    double temp;
    double t1 = v[i] / a;
    double s1 = 0.5 * a * t1 * t1;
    if (s1 - d > 1e-10) {
      temp = sqrt(2 * d / a);
    } else {
      temp = t1 + (d - s1) / v[i];
    }
    temp += t[i];
    if (i == 0)
      ans[i] = temp;
    else {
      if (temp - ans[i - 1] < 1e-10)
        ans[i] = ans[i - 1];
      else
        ans[i] = temp;
    }
  }
  for (i = 0; i < n; i++) {
    printf("%.12lf\n", ans[i]);
  }
  return 0;
}
