Convert a Binary Tree into its Mirror Tree


Mirror of a Tree: Mirror of a Binary Tree T is another Binary Tree M(T) with left and right children of all non-leaf nodes interchanged.

MirrorTree1


Code:

package trees;

public class N1804_MirrorTree {

    Node root = null;

    static void convertToMirror(Node node){

        if(node == null){
            return;
        }

        Node temp = node.left;
        node.left = node.right;
        node.right = temp;

        convertToMirror(node.left);
        convertToMirror(node.right);
    }

    static void printTree(Node node){

        if(node == null)
            return;

        printTree(node.left);
        System.out.print(node.data+" ");
        printTree(node.right);
    }

    public static void main(String[] args){

        N1804_MirrorTree tree = new N1804_MirrorTree();
        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);
       
        printTree(tree.root);
        System.out.println();
       
        convertToMirror(tree.root);
        printTree(tree.root);

    }


}


Output:

4 2 5 1 3
3 1 5 2 4

Reference:

https://www.geeksforgeeks.org/write-an-efficient-c-function-to-convert-a-tree-into-its-mirror-tree/

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