#include <bits/stdc++.h>
using namespace std;
const double EPS = 1e-9;
int main() {
  int i;
  double n, a, d;
  double t[100010], v[100010];
  scanf("%lf %lf %lf", &n, &a, &d);
  for (i = 0; i < n; ++i) scanf("%lf %lf", &t[i], &v[i]);
  double tt, lastt = 0;
  for (i = 0; i < n; ++i) {
    double ta = v[i] / a, da = ta / 2 * v[i];
    if (da <= d)
      tt = t[i] + ta + (d - da) / v[i];
    else
      tt = t[i] + (ta = sqrt(2 * d / a));
    printf("%.10lf\n", max(tt, lastt));
    lastt = max(lastt, tt);
  }
  return 0;
}
