#include <bits/stdc++.h>
using namespace std;
long long mod = 1000000007;
const int INF = 1e9;
const long long LINF = 1e18;
long long mod_sum() { return 0LL; }
template <typename T, typename... Args>
T mod_sum(T a, Args... args) {
  return ((a + mod_sum(args...)) % mod + mod) % mod;
}
long long mod_prod() { return 1LL; }
template <typename T, typename... Args>
T mod_prod(T a, Args... args) {
  return (a * mod_prod(args...)) % mod;
}
long long solve() {
  long double n, a, d;
  cin >> n >> a >> d;
  long double mx = 0;
  while (n--) {
    long double v, t0;
    cin >> t0 >> v;
    if (sqrt(2 * a * d) < v) {
      long double ans = sqrt(2 * d / a) + t0;
      if (ans < mx) ans = mx;
      printf("%0.10Lf\n", ans);
      mx = max(ans, mx);
      continue;
    }
    long double t1 = v / a;
    long double d1 = v * v / (2 * a);
    long double t2 = (d - d1) / v;
    long double ans = t0 + t1 + t2;
    if (ans < mx) ans = mx;
    printf("%0.10Lf\n", ans);
    mx = max(ans, mx);
  }
  return 0;
}
int main() {
  ios_base::sync_with_stdio(0);
  cin.tie(0);
  cout.tie(0);
  long long t = 1;
  while (t--) solve();
  return 0;
}
