#include <bits/stdc++.h>
using namespace std;
int n, a, d;
int main() {
  scanf("%d%d%d", &n, &a, &d);
  double ans = 0;
  for (int i = 0; i < (n); i++) {
    int dt, v;
    scanf("%d%d", &dt, &v);
    double t = dt, s = double(v) / (2 * a) * v;
    if (s > d + 1e-9) {
      double u = sqrt(double(d) * 2 * a);
      t += u / a;
    } else
      t += (d - s) / v + double(v) / a;
    ans = max(ans, t);
    printf("%.6lf\n", ans);
  }
}
