DeleteNode.c

#include <stdio.h>
#include <stdlib.h>

typedef struct Node {
  int data;
  struct Node *next;
} Node;

Node * createNode(int val){
  Node *temp = (Node *)malloc(sizeof(Node));
  if(temp){
    temp->data = val;
    temp->next = NULL;
  }
  return temp;
}
/* This function inserts node at the head of linked list */
void push(Node **headRef, int data){
	Node * newNode  = createNode(data);
	newNode->next = *headRef;
	*headRef  = newNode;
}
void printList(Node *head){
	while(head){
		printf("%d->", head->data);
		head = head->next;
	}
	printf("Null");
}

/*Function deletes a node from linked list given its pointer
It does not work for last node deletion */
void deleteNode(Node *nodeToDelete){
	//Wrong input
	if(!nodeToDelete) return;
	
	if(!nodeToDelete->next){
		printf("Last node cannot be delete with this method");
		return;
	}
	
	Node *nextNode = nodeToDelete->next;
	//Copy value of next node
	nodeToDelete->data = nextNode->data;
	//Link nodes
	nodeToDelete->next = nextNode->next;
	//Delete next node
	free(nextNode);
	
	return;
}

int main(void) {
	
	Node *head = NULL;
	push(&head, 3);
	push(&head, 4);
	Node * nodeToDelete = head;
	push(&head, 5);
	push(&head, 6);
	push(&head, 7);
	printf("\nOriginal list :");
	printList(head);
  	deleteNode(nodeToDelete);
  	printf("\nList after deletion :");
  	printList(head);
	return 0;
}