Driver code
public static void Main ( String [ ] args ) { ExpressionTree et = new ExpressionTree ( ) ; String postfix = " ab + ef * g * - " ; char [ ] charArray = postfix . ToCharArray ( ) ; Node root = et . constructTree ( charArray ) ; Console . WriteLine ( " infix ▁ expression ▁ is " ) ; et . inorder ( root ) ; } }