Print Postorder traversal from given Inorder and Preorder traversals without constructing the tree

printPreorder.java

class Node 
{
	char data;
	Node left, right;

	Node(char item) 
	{
		data = item;
		left = right = null;
	}
}

class BinaryTree 
{
	Node root;
	int preIndex = 0;

	void buildTree(char in[], char pre[], int inStrt, int inEnd) 
	{
		if (inStrt > inEnd) 
			return;

		/* Pick current node from Preorder traversal using preIndex
		and increment preIndex */
		Node tNode = new Node(pre[preIndex++]);

		/* If this node has no children then return */
		if (inStrt == inEnd){
			System.out.println(tNode.data + " ");
			return;
		}

		/* Else find the index of this node in Inorder traversal */
		int inIndex = search(in, inStrt, inEnd, tNode.data);

		/* Using index in Inorder traversal, construct left and
		right subtress */
		 buildTree(in, pre, inStrt, inIndex - 1);
		buildTree(in, pre, inIndex + 1, inEnd);
        
        System.out.println(tNode.data + " ");
		
	}

	int search(char arr[], int strt, int end, char value) 
	{
		int i;
		for (i = strt; i <= end; i++) 
		{
			if (arr[i] == value)
				return i;
		}
		return i;
	}

	// driver program to test above functions
	public static void main(String args[]) 
	{
		BinaryTree tree = new BinaryTree();
		char in[] = new char[]{'D', 'B', 'E', 'A', 'F', 'C'};
		char pre[] = new char[]{'A', 'B', 'D', 'E', 'C', 'F'};
		int len = in.length;
		tree.buildTree(in, pre, 0, len - 1);
	}
}