binary trees + / - figure expression tree for /( traversals to produce the correct expression trying to determine the minimum sets of parentheses that are required can be difficultbut we can easily create fully parenthesized expression(( ( ( ))we know an inorder traversal produces the correct ordering of operators and operands for the resulting expression we just have to figure out how to insert the parentheses in fully parenthesized expressiona pair of parentheses encloses each operator and its operands thuswe need to enclose each subtree within pair of parenthesesas illustrated in figure left parenthesis needs to be printed before subtree is visitedwhereas the right one needs to be printed after the subtree has been visited we can combine all three traversals in single recursive operationas shown in listing figure expression tree with braces grouping the subtrees tree evaluation given an algebraic expression represented as binary treewe can develop an algorithm to evaluate the expression each subtree represents valid subexpression with those lower in the tree having higher precedence thusthe two subtrees of each interior node must be evaluated before the node itself for examplein the expression tree from figure the addition operation cannot be performed until both subexpressions (the multiplication and the divisionhave been computed as