This needs to be done in C++. Please comment code and make sure you have the appriopriate input validation.

Write a program to build a binary tree (using pointers) from a string of characters and print out the binary tree in preorder, inorder, postorder and level-order The input string is a preorder order representation of a binary tree. In particular, a dot/period signifies an empty subtree in that branch. There should not be any node that holds the character ".". Character "." is not part of the allowable character in the node. You have to check whether the input string is a correct representation of a possible binary tree or not. You are NOT building a binary search tree. The binary tree that you build is not necessarily full or complete. You can assume that each node consists of one character only Write a program to build a binary tree (using pointers) from a string of characters and print out the binary tree in preorder, inorder, postorder and level-order The input string is a preorder order representation of a binary tree. In particular, a dot/period signifies an empty subtree in that branch. There should not be any node that holds the character ".". Character "." is not part of the allowable character in the node. You have to check whether the input string is a correct representation of a possible binary tree or not. You are NOT building a binary search tree. The binary tree that you build is not necessarily full or complete. You can assume that each node consists of one character only