Data structure review notes-binary tree 2 and binary tree

Data structure review notes-binary tree 2 and binary tree

Non-recursive traversal of Binary Trees:

Non-recursive Traversal Algorithm
The basic idea for implementing non-recursive algorithms: Use stacks:

Void InOrderTraversal (BinTree BT) {BinTree T = BT; Stack S = CreatStack (MaxSize);/* Create and initialize Stack S */while (T |! IsEmpty (S) {while (T)/* always to the Left and press the node along the way into the stack */{Push (S, T); T = T-> Left ;} if (! IsEmpty (S) {T = Pop (S);/* node Pop-up stack */printf ("% 5d", T-> Data);/* (ACCESS) print node */T = T-> Right;/* Turn to the Right subtree */}}}

 

Void InOrderTraversal (BinTree BT) {BinTree T = BT; Stack S = CreatStack (MaxSize);/* Create and initialize Stack S */while (T |! IsEmpty (S) {while (T)/* always to the left and press the node along the way into the stack */{Push (S, T); printf ("% 5d ", t-> Data);/* (ACCESS) print node */T = T-> Left;} if (! IsEmpty (S) {T = Pop (S);/* node Pop-up stack */T = T-> Right;/* Turn to the Right subtree */}}}

Void PostOrder_NoRecurse (BinTree BT, void (* Do) (BinTree) // non-recursive post-order traversal {BinTree T = BT; Stack s = CreateStack (20 ); int Tag [20]; // Tag is used to mark the elements in the stack for the first time. It is an integer stack while (T |! Stack_IsEmpty (s) {while (T) // every time a new element is encountered, it is controlled here {Stack_Push (s, T ); // put the stack and cycle to its leftmost Tag [s-> size-1] = 0; T = T-> Left;} while (! T &&! Stack_IsEmpty (s) {T = Stack_Pop (s); // retrieves an element in the stack and determines its Tag if (Tag [s-> size]) {(* Do) (T); // Tag! = 0 indicates that the node is met for the third time and T = 0 is operated on it; // set T to 0 to trigger the While condition, continue loop} else // Tag = 0 indicates the second encounter (the first time is to set the Tag to 0) {if (! T-> Right) (* Do) (T); // if the Right son does not exist, else {Stack_Push (s, T) is output directly; // if the Right son exists, put it back into the stack Tag [s-> size-1] ++; // and add the corresponding Tag} T = T-> Right; // return the Right son. Note: If the right son does not exist, the While continue loop will be triggered} // otherwise, it will be determined that a new element will jump out of the loop and the large While loop outside will be continued }}}

Are two traversal sequences used to determine a binary tree?

Is it known that any two of the three traversal sequences can uniquely identify a binary tree? We know that, no matter which type, we must first prophet sequential traversal.

For example, the first and middle order traversal sequences are used to determine a binary tree.
Analysis 〗
1. traverse the first node of the sequence to determine the root node;
2. Split the Left and Right sub-sequences in the central traversal Sequence Based on the Root Node
3. The left and right subtree are recursively decomposed using the same method.

Exercise: paste it in a few days.