#include <bits/stdc++.h>
const long long mod = 1e9 + 7;
using namespace std;
inline int read() {
  register int x = 0, f = 1, ch = getchar();
  while (!isdigit(ch)) {
    if (ch == '-') f = -1;
    ch = getchar();
  }
  while (isdigit(ch)) {
    x = x * 10 + ch - '0';
    ch = getchar();
  }
  return x * f;
}
long double f[100005];
int32_t main() {
  int n, a, d;
  scanf("%d%d%d", &n, &a, &d);
  for (int i = 1; i <= n; i++) {
    long double t, v;
    cin >> t >> v;
    if (v * v / 2.0 / a < d * 1.0)
      f[i] = d / v - v / 2.0 / a + v / a + t;
    else
      f[i] = sqrt(2.0 * d / a) + t;
    if (i > 1 && f[i] < f[i - 1]) {
      f[i] = f[i - 1];
    }
  }
  for (int i = 1; i <= n; i++) {
    printf("%.10Lf\n", f[i]);
  }
  return 0;
}
