#include <bits/stdc++.h>
int main() {
  double n, a, s;
  while (scanf("%lf%lf%lf", &n, &a, &s) != EOF) {
    double t, v, max = 0;
    while (n--) {
      scanf("%lf%lf", &t, &v);
      double time = t;
      double sum = v * v * 1.0 / (2.0 * a);
      if (sum <= s) {
        sum = s - sum;
        time += (v * 1.0 / a + sum * 1.0 / v);
      } else
        time += sqrt(2.0 * s / a);
      if (time > max) max = time;
      if (time < max) time = max;
      printf("%.4f\n", time);
    }
  }
  return 0;
}
