class Node{
        Node(int k){
            this.k = k;
        }
        int k;
        Node right;
        Node left;
    }

public class Testing {
    static void preOrder(Node n){
        if(n==null);

        else{
            preOrder(n.left);
            preOrder(n.right);
            System.out.println(n.k);
        }
    }

    static Node del_leaves(Node n,int k){
       if(n==null)
           return null;
       else{
           Node l=null,r=null;
           if(n.left!=null)
               l = del_leaves(n.left,k);
           if(n.right!=null)
               r = del_leaves(n.right,k);
           if(l==null&&r==null&&n.k==k){
               n=null;
               return n;
           }
           else
               return n;
       }
    }
public static void main(String args[]){
    Node root = new Node(10);
    Node a = new Node(5);
    Node b = new Node(5);
    Node c = new Node(5);
    Node d = new Node(5);
    Node e = new Node(5);
    root.left=a;
    root.right=b;
    a.left=c;
    a.right=d;
    b.left=e;
    preOrder(root);
    Node ret_root = del_leaves(root,5);
    System.out.println("*****************************");
    preOrder(ret_root);
}

}