#include <bits/stdc++.h>
using namespace std;
double v[1000006], t[1000006];
int main() {
  int n, i;
  double a, d;
  scanf("%d", &n);
  scanf("%lf", &a);
  scanf("%lf", &d);
  for (i = 0; i < n; i++) {
    scanf("%lf", &t[i]);
    scanf("%lf", &v[i]);
  }
  double t0 = sqrt(2 * d / a);
  double v0 = a * t0;
  double prevt = -1, curt;
  for (i = 0; i < n; i++) {
    if (v[i] >= v0) {
      curt = t[i] + t0;
    } else {
      double t1 = v[i] / a;
      double d1 = 0.5 * a * t1 * t1;
      double t2 = (d - d1) / v[i];
      curt = t[i] + t1 + t2;
    }
    curt = max(curt, prevt);
    printf("%.9lf\n", curt);
    prevt = curt;
  }
  return 0;
}
