Linked List program using C

#include<stdio.h> #include<stdlib.h> struct node { int data; struct node *next; } *head = NULL; int isEmpty() { return (head==NULL); } void insert_At_Beginning(int value) { struct node *temp = (struct node*)malloc(sizeof(struct node)); temp -> data = value; temp -> next = head; head = temp; } void insert_At_End(int value) { struct node *temp = (struct node*)malloc(sizeof(struct node)); struct node *current = head; temp -> data = value; temp -> next = NULL; if(isEmpty()) { head = temp; return; } while(current -> next != NULL) current = current -> next; current -> next = temp; } void insert_After_Value(int desired, int value) { struct node *current = head; while(current != NULL && current -> data != desired) current = current -> next; if(current == NULL) printf("Element %d is not in the list.\n",desired); else { struct node *temp = (struct node*)malloc(sizeof(struct node)); temp -> data = value; temp -> next = current -> next; current -> next = temp; } } void delete_At_Beginning() { if(isEmpty()) printf("List is empty.\n"); else { struct node *temp = head; head = head -> next; temp -> next = NULL; free(temp); } } void delete_At_End() { if(isEmpty()) { printf("List is empty.\n"); return ; } struct node *temp = head, *prev; if(head -> next == NULL) { head = NULL; free(temp); return ; } while(temp -> next != NULL) { prev = temp; temp = temp -> next; } prev -> next = temp -> next; temp -> next = NULL; free(temp); } void delete_With_Value(int desired) { if(isEmpty()) { printf("List is empty.\n"); return ; } struct node *temp = head, *prev; if(head -> data == desired) { head = head -> next; temp -> next = NULL; free(temp); return ; } while(temp != NULL && temp -> data != desired) { prev = temp; temp = temp -> next; } if(temp == NULL) printf("Element %d not in the list\n",desired); else { prev -> next = temp -> next; temp -> next = NULL; free(temp); } } void search(int desired) { struct node *temp = head; while(temp != NULL && temp -> data != desired) temp = temp -> next; if(temp == NULL) printf("Element %d not found in the list.\n",desired); else printf("Element %d is present in the list.\n",desired); } void printList() { if(isEmpty()) { printf("List is Empty\n"); return ; } struct node *current = head; while(current -> next != NULL) { printf("%d -> ",current->data); current = current -> next; } printf("%d\n",current->data); } void iterative_Reverse() { struct node* prev = NULL; struct node* current = head; struct node* next; while (current != NULL) { next = current->next; current->next = prev; prev = current; current = next; } head = prev; } int main() { int i; for(i = 0; i < 5; i++) insert_At_Beginning(i); printList(); for(i = 5; i < 10; i++) insert_At_End(i); printList(); insert_After_Value(5, 9); insert_After_Value(10, 9); printList(); for(i = 0; i < 3; i++) delete_At_End(); printList(); for(i = 0; i < 3; i++) delete_At_Beginning(); printList(); delete_With_Value(1); delete_With_Value(5); printList(); iterative_Reverse(head); printList(); search(6); search(8); }

C Program for linked list