#include <bits/stdc++.h>
using namespace std;
const long long modn = 1000000007;
inline long long mod(long long x) { return x % modn; }
int t[112345];
double v[112345];
int main() {
  int i, j, n;
  double a, d;
  scanf("%d %lf %lf", &n, &a, &d);
  double mx = -1. / 0.;
  for (i = 0; i < n; i++) {
    scanf("%d %lf", &t[i], &v[i]);
    double dist = v[i] * v[i] / (2. * a);
    double tim = t[i];
    if (dist > d) {
      tim += sqrt((2. * d) / a);
    } else {
      tim += v[i] / a;
      tim += (d - dist) / v[i];
    }
    if (tim < mx) tim = mx;
    mx = tim;
    printf("%.10lf\n", tim);
  }
}
