Delete last node of linked list in c

C program for Delete last node of linked list. Here problem description and explanation.

/*
    C program for
    Delete the last node of Singly linked list
*/
#include <stdio.h>
#include <stdlib.h>

// Linked List LinkNode
struct LinkNode
{
	int data;
	struct LinkNode *next;
};
// Singly linked list 
struct SingleLL
{
	struct LinkNode *head;
	struct LinkNode *tail;
};
// Returns the new linked list
struct SingleLL *newLinkedList()
{
	// Create memory of head and tail Nodes
	struct SingleLL *sll = (struct SingleLL *)
	malloc(sizeof(struct SingleLL));
	if (sll == NULL)
	{
		printf("Memory overflow\n");
	}
	else
	{
		sll->head = NULL;
		sll->tail = NULL;
	}
	return sll;
}
// Handles the request of adding new node at end of linked list
void addNode(struct SingleLL *sll, int data)
{
	// Create dynamic node
	struct LinkNode *node = (struct LinkNode *)
	malloc(sizeof(struct LinkNode));
	if (node == NULL)
	{
		printf("Memory overflow to Create LinkNode\n");
		return;
	}
	else
	{
		// Set initial node value
		node->data = data;
		node->next = NULL;
	}
	if (sll->head == NULL)
	{
		sll->head = node;
	}
	else
	{
		sll->tail->next = node;
	}
	sll->tail = node;
}
// Display linked list element
void display(struct LinkNode *node)
{
	if (node == NULL)
	{
		return;
	}
	struct LinkNode *temp = node;
	// iterating linked list elements
	while (temp != NULL)
	{
		printf(" %d →", temp->data);
		// Visit to next node
		temp = temp->next;
	}
	printf(" NULL\n");
}
// Delete last node of singly linked list
void deleteLastNode(struct SingleLL *sll)
{
	if (sll->head == NULL)
	{
		printf("Empty Linked List\n");
		return;
	}
	else
	{
		struct LinkNode *temp = sll->head;
		struct LinkNode *find = NULL;
		// Find second last node
		while (temp->next != NULL)
		{
			find = temp;
			temp = temp->next;
		}
		if (find == NULL)
		{
			// Delete head node of linked list
			sll->head = NULL;
			sll->tail = NULL;
		}
		else
		{
			sll->tail = find;
			find->next = NULL;
		}
		// remove last element
		free(temp);
		temp = NULL;
	}
}
int main(int argc, char
	const *argv[])
{
	struct SingleLL *sll = newLinkedList();
	// Linked list
	// 1 → 2 → 3 → 4 → 5 → 6 → NULL
	addNode(sll, 1);
	addNode(sll, 2);
	addNode(sll, 3);
	addNode(sll, 4);
	addNode(sll, 5);
	addNode(sll, 6);
	printf(" Before Delete \n");
	display(sll->head);
	deleteLastNode(sll);
	printf(" After Delete \n");
	display(sll->head);
	return 0;
}

Output

 Before Delete
 1 → 2 → 3 → 4 → 5 → 6 → NULL
 After Delete
 1 → 2 → 3 → 4 → 5 → NULL


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