Prove that the algorithms printExpression and evalExpr correctly print out and evaluate an arithmetic expression represented by a binary tree.

Hint: Use induction and the recursive definition of a binary tree

Algorithm printExpression(v) if v.isExternal() print("() inOrder(v.left) print(v.element)) if v.isExternal() inOrder(v.rightO) print (")') Algorithm printExpression(v) if v.isExternal() print("() inOrder(v.left) print(v.element)) if v.isExternal() inOrder(v.rightO) print (")')