source_code: import java.util.*;
  
  public class PC1229 {
  
  	public static void main(String[] args){
  		Scanner sc = new Scanner(System.in);
  		int n = sc.nextInt();
  		int r = sc.nextInt();
  		int[] x = new int[n];
  		for(int i = 0; i < n; i++){
  			x[i] = sc.nextInt();
  		}
  		double[] ans = new double[n];
  		for(int i = 0; i < n; i++){
  			double maxY = r;
  			for(int j = 0; j < i; j++){
  				if(x[j] <= x[i] + 2*r && x[j] >= x[i] - 2*r){
  					maxY = Math.max(maxY, ans[j] + Math.sqrt(4 * r * r - (Math.abs(x[i] - x[j])) * (Math.abs(x[i] - x[j]))));
  				}
  			}
  			ans[i] = maxY;
  		}
  		for(int i = 0; i < n; i++){
  			System.out.println(ans[i]);
  		}
  		sc.close();
  	}
  	
  }
  