Print Ancestors of a given node in a binary tree


Problem link


Code:

public class Ancestors {
   
    Node root;
   
    boolean isAncestor(Node node, int data){
        if(node == null)
            return false;
        if(node.data == data)
            return true;
        if(isAncestor(node.left, data) || isAncestor(node.right, data)){
            System.out.print(node.data+" ");
            return true;
        }
       
        return false;
    }
   
    public static void main(String[] args){
        Ancestors tree = new Ancestors();

        tree.root = new Node(1);
        /* Construct the following binary tree
        1
      /   \
     2     3
    /  \
   4    5
  /
 7
         */
        tree.root = new Node(1);
        tree.root.left = new Node(2);
        tree.root.right = new Node(3);
        tree.root.left.left = new Node(4);
        tree.root.left.right = new Node(5);
        tree.root.left.left.left = new Node(7);

        tree.isAncestor(tree.root, 7);
    }

}


Output:

4 2 1

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