Linked complete binary tree & its creation | Program for linked implementation of complete binary tree ; For Queue Size ; A tree node ; A queue node ; A utility function to create a new tree node ; A utility function to create a new Queue ; Standard Queue Functions ; A utility function to check if a tree node has both left and right children ; Function to insert a new node in complete binary tree ; Create a new node for given data ; If the tree is empty , initialize the root with new node . ; get the front node of the queue . ; If the left child of this front node doesn t exist , set the left child as the new node ; If the right child of this front node doesn t exist , set the right child as the new node ; If the front node has both the left child and right child , Dequeue ( ) it . ; Enqueue ( ) the new node for later insertions ; Standard level order traversal to test above function ; Driver program to test above functions
#include <stdio.h> NEW_LINE #include <stdlib.h> NEW_LINE #define SIZE  50 NEW_LINE struct node { int data ; struct node * right , * left ; } ; struct Queue { int front , rear ; int size ; struct node * * array ; } ; struct node * newNode ( int data ) { struct node * temp = ( struct node * ) malloc ( sizeof ( struct node ) ) ; temp -> data = data ; temp -> left = temp -> right = NULL ; return temp ; } struct Queue * createQueue ( int size ) { struct Queue * queue = ( struct Queue * ) malloc ( sizeof ( struct Queue ) ) ; queue -> front = queue -> rear = -1 ; queue -> size = size ; queue -> array = ( struct node * * ) malloc ( queue -> size * sizeof ( struct node * ) ) ; int i ; for ( i = 0 ; i < size ; ++ i ) queue -> array [ i ] = NULL ; return queue ; } int isEmpty ( struct Queue * queue ) { return queue -> front == -1 ; } int isFull ( struct Queue * queue ) { return queue -> rear == queue -> size - 1 ; } int hasOnlyOneItem ( struct Queue * queue ) { return queue -> front == queue -> rear ; } void Enqueue ( struct node * root , struct Queue * queue ) { if ( isFull ( queue ) ) return ; queue -> array [ ++ queue -> rear ] = root ; if ( isEmpty ( queue ) ) ++ queue -> front ; } struct node * Dequeue ( struct Queue * queue ) { if ( isEmpty ( queue ) ) return NULL ; struct node * temp = queue -> array [ queue -> front ] ; if ( hasOnlyOneItem ( queue ) ) queue -> front = queue -> rear = -1 ; else ++ queue -> front ; return temp ; } struct node * getFront ( struct Queue * queue ) { return queue -> array [ queue -> front ] ; } int hasBothChild ( struct node * temp ) { return temp && temp -> left && temp -> right ; } void insert ( struct node * * root , int data , struct Queue * queue ) { struct node * temp = newNode ( data ) ; if ( ! * root ) * root = temp ; else { struct node * front = getFront ( queue ) ; if ( ! front -> left ) front -> left = temp ; else if ( ! front -> right ) front -> right = temp ; if ( hasBothChild ( front ) ) Dequeue ( queue ) ; } Enqueue ( temp , queue ) ; } void levelOrder ( struct node * root ) { struct Queue * queue = createQueue ( SIZE ) ; Enqueue ( root , queue ) ; while ( ! isEmpty ( queue ) ) { struct node * temp = Dequeue ( queue ) ; printf ( " % d ▁ " , temp -> data ) ; if ( temp -> left ) Enqueue ( temp -> left , queue ) ; if ( temp -> right ) Enqueue ( temp -> right , queue ) ; } } int main ( ) { struct node * root = NULL ; struct Queue * queue = createQueue ( SIZE ) ; int i ; for ( i = 1 ; i <= 12 ; ++ i ) insert ( & root , i , queue ) ; levelOrder ( root ) ; return 0 ; }