C Programming Code Examples C > Linked Lists Code Examples Program that takes an Ordered Binary tree & Rearranges the Internal Pointers to make Program that takes an Ordered Binary tree & Rearranges the Internal Pointers to make a Circular Doubly Linked List out of the Tree Nodes #include <stdio.h> #include <stdlib.h> struct node { int j; struct node *left; struct node *right; int used; }; void create(struct node **); void release(struct node **); void display(struct node *, int); struct node * transformdet(struct node *); struct node * transform(struct node *); int main() { struct node *root = NULL, *head; printf("Creating binary tree:\n"); create (&root); printf("Displaying binary tree:\n"); display(root, 0); head = transform(root); printf("\nDisplaying circular linked list:\n"); display(head, 1); root->left->right = NULL; release(&root); return 0; } struct node * transformdet(struct node *root) { struct node *left, *right; if (root == NULL) { return root; } if (root->left != NULL) { left = transformdet(root->left); while (left->right != NULL) { left = left->right; } left->right = root; root->left = left; } if (root->right != NULL) { right = transformdet(root->right); while (right->left != NULL) { right = right->left; } right->left = root; root->right = right; } return root; } struct node * transform(struct node *root) { struct node *rear; if (root == NULL) { return root; } root = transformdet(root); rear = root; while (root->left != NULL) { root = root->left; } while (rear->right != NULL) { rear = rear->right; } root->left = rear; rear->right = root; return (root); } void create(struct node **root) { struct node *temp, *p, *q; int a, ch; do { p = *root; printf("Enter a number in the tree: "); scanf("%d", &a); temp = (struct node *)malloc(sizeof(struct node)); temp->j = a; temp->used = 0; temp->left = temp->right = NULL; if (*root == NULL) { *root = temp; } else { while (p != NULL) { q = p; if (p->j >= temp->j) { p = p->right; } else { p = p->left; } } if (q->j >= temp->j) { q->right = temp; } else { q->left = temp; } } printf("Do you want to add more numbers? [1/0]\n"); scanf("%d", &ch); } while (ch != 0); } void display(struct node *root, int n) { struct node *temp; if (root != NULL && !n) { display(root->left, 0); printf("%d ", root->j); display(root->right, 0); } else if (root != NULL && n) { temp = root; printf("%d ", temp->j); temp = temp->right; while (temp != root) { printf("%d ", temp->j); temp = temp->right; } printf("\n"); } } void release(struct node **root) { if (*root != NULL) { release(&(*root)->right); free(*root); } }
