#include <bits/stdc++.h>
using namespace std;
;
struct _dbg {
  template <class T>
  _dbg& operator,(const T& v) {
    cerr << v << " ";
    return *this;
  };
};
_dbg _d;
void go();
int main() {
  ios_base::sync_with_stdio(0);
  cin.tie(0);
  go();
};
int N;
double mt, tf, a, d, t, v;
void go() {
  cin >> N >> a >> d;
  for (int i = 0, _i = (N); i < _i; ++i) {
    cin >> t >> v;
    mt = max(mt, t + (v * v / (2 * a) > d ? sqrt(2 * d / a)
                                          : v / a + (d - v * v / (2 * a)) / v));
    printf("%.12f\n", mt);
  };
};
