#include <bits/stdc++.h>
int main() {
  int n;
  double a, d, t, v, x, y;
  while (scanf("%d%lf%lf", &n, &a, &d) != EOF) {
    y = 0.0;
    while (n--) {
      scanf("%lf%lf", &t, &v);
      if (d - v * v / 2 / a > 0)
        x = t + v / a + (d - v * v / 2 / a) / v;
      else {
        x = t + sqrt(2 * d / a);
      }
      if (x <= y)
        printf("%.10lf\n", y);
      else {
        printf("%.10lf\n", x);
        y = x;
      }
    }
  }
  return 0;
}
