#include <bits/stdc++.h>
using namespace std;
int n;
double a, d, t, v, cur = 0, c;
double gett(double d, double a, double v) {
  double t = v / a;
  if (a * t * t / 2 > d) {
    double r = t, l = 0, m;
    for (int i = 0; i < 100; ++i) {
      m = (l + r) / 2;
      if (a * m * m / 2 > d)
        r = m;
      else
        l = m;
    }
    return m;
  }
  d -= a * t * t / 2;
  return t + d / v;
}
int main(void) {
  int i;
  cin >> n >> a >> d;
  for (i = 0; i < n; ++i) {
    cin >> t >> v;
    c = t + gett(d, a, v);
    if (c < cur)
      printf("%.10lf\n", cur);
    else {
      printf("%.10lf\n", c);
      cur = c;
    }
  }
  return 0;
}
