binary trees when you're done evaluating the postfix stringyou pop the one remaining item off the stack somewhat amazinglythis item is complete tree depicting the algebraic expression you can see the prefix and infix representations of the original postfix (and recover the postfix expressionby traversing the tree as we described we'll leave an implementation of this process as an exercise finding maximum and minimum values incidentallywe should note how easy it is to find the maximum and minimum values in binary search tree in factthis process is so easy we don' include it as an option in the workshop appletnor show code for it in listing stillunderstanding how it works is important for the minimumgo to the left child of the rootthen go to the left child of that childand so onuntil you come to node that has no left child this node is the minimumas shown in figure minimum figure minimum value of tree here' some code that returns the node with the minimum key valuepublic node minimum(/returns node with minimum key value node currentlastcurrent root/start at root while(current !null/until the bottom