#include <bits/stdc++.h>
using namespace std;
int trolleys, accel, dist;
int main() {
  scanf("%d%d%d", &trolleys, &accel, &dist);
  double mintime = 0.0, finalsp = sqrt((double)2 * accel * dist);
  for (int i = 1; i <= trolleys; ++i) {
    int speed, start;
    scanf("%d%d", &start, &speed);
    if (speed >= finalsp)
      mintime = max(mintime, (double)start + dist * 2 / finalsp);
    else {
      double point = (double)speed / accel;
      mintime = max(mintime, (double)start + point +
                                 (dist - point * 0.5 * speed) / speed);
    }
    printf("%lf\n", mintime);
  }
  return 0;
}
