#include <bits/stdc++.h>
using namespace std;
int n, a, d, t[100005], v[100005];
int main() {
  scanf("%d%d%d", &n, &a, &d);
  for (int i = 0; i < n; ++i) scanf("%d%d", &t[i], &v[i]);
  double last = -1;
  for (int i = 0; i < n; ++i) {
    double now;
    double t0 = (double)v[i] / a, s = 0.5 * a * t0 * t0;
    if (s > (double)d) {
      now = sqrt(2.0 * d / a) + t[i];
    } else
      now = t0 + ((double)d - s) / v[i] + t[i];
    if (now > last) {
      printf("%.10lf\n", now);
      last = now;
    } else
      printf("%.10lf\n", last);
  }
  return 0;
}
