#include <bits/stdc++.h>
using namespace std;
struct bus {
  double t, v;
  double cost, time;
};
bus bus[100000];
int main() {
  int n, a, d;
  scanf("%d%d%d", &n, &a, &d);
  double fastest = 0.0;
  double x, y;
  for (int i = 0; i < n; i++) {
    scanf("%lf%lf", &bus[i].t, &bus[i].v);
    x = (d - bus[i].v * bus[i].v / (2.0 * a)) / bus[i].v;
    y = bus[i].t + (bus[i].v / a) + x;
    if (x < 0) {
      y = bus[i].t + sqrt(2.0 * d / (double)a);
    }
    if (fastest <= y) fastest = y;
    printf("%.10f\n", fastest);
  }
}
