Description

To delete a node from end of the singly linked list - 
Case 1: check if list is empty 
	Show message that list is empty.
Case 2: When list has only one elements
	step 1: Assign the address of head to temporary variable
	step 2: Assign NULL to head.
	step 3: Free the memory occupied by node
Case 3: When linked list has more than one elements
	step 1: Traverse the list to reach last node.
	step 2: Maintain one more field which contain the address of previous node.
	step 3: Assign the NULL to the address field of previous node of last node.
	step 4: Free the memory occupied by last node.

Note: Here head contains the address of first node

C/C++

/* C Program To Delete a Node from end in singly linked list */
//Save it as delete_node_end_singly_linked_list.java

#include<stdio.h>
#include<malloc.h>
struct node *create(int);
void display(struct node *);
struct node *delete_end(struct node *);

//Declaring node
struct node{
    int data;
    struct node *next;
};

int main(){
    int n;
    struct node *head;
    printf("Enter number of nodes : ");
    scanf("%d",&n);
	
    //Calling function to create node
    head=create(n);
	
    //Calling function to display list
    display(head);
	
    //Code to delete a node from end
    head=delete_end(head);
    printf("\nThe linked list after deletion of node from end - \n");
	
    //Calling function to display list after deletion of a node from end
    display(head);

    return 0;
}

struct node *create(int n){
    int i;
    struct node *head=NULL;
    struct node *ptr,*newNode;

    for(i=0;i<n;i++){
		
        //Creating a new node
        newNode=(struct node*)malloc(sizeof(struct node*));
		
        //Assigning data to newly created node
        printf("Enter the value of %d node : ",i+1);
        scanf("%d",&newNode->data);
        newNode->next=NULL;
		
        /*If list is empty assign the address of newly created node to head*/
        if(head==NULL){
            head=newNode;
        }else{
			
            /* If list already have few elements then loop through
			list and add newly created node after given node*/
            ptr=head;
            while(ptr->next!=NULL){
                ptr=ptr->next;
            }
            ptr->next=newNode;
        }
    }
    return head;
}

void display(struct node *head){
    struct node *ptr;
	
    //If list is empty
    if(head==NULL){
        printf("The linked list is empty");
    }else{
		
        /*If list has elements then loop through the loop and
		print elements one by one in sequential manner*/
        ptr=head;
        while(ptr!=NULL){
            printf("The node value = %d and their address = %u\n",ptr->data,ptr);
            ptr=ptr->next;
        }
    }
}

//Function to delete a node from end
struct node *delete_end(struct node *head){
    struct node *preptr, *ptr;
	
    //If list do not have any element, show proper message
    if(head==NULL){
        printf("\nLink list is empty..No node to delete!!");
    }else if(head->next==NULL){
		
        //If list have only one element
        ptr=head;
        head=NULL;
        free(ptr);
    }else{
		
        //If list have more than one elements
        ptr=head;
        while(ptr->next!=NULL){
            preptr=ptr;
            ptr=ptr->next;
        }
        preptr->next=NULL;
        free(ptr);
    }
    return head;
}

Input:
Enter number of nodes : 5
Enter the value of 1 node : 1
Enter the value of 2 node : 2
Enter the value of 3 node : 3
Enter the value of 4 node : 4
Enter the value of 5 node : 5
The node value = 1 and their address = 5508432
The node value = 2 and their address = 5508464
The node value = 3 and their address = 5508480
The node value = 4 and their address = 5508496
The node value = 5 and their address = 5508512

Output:
The linked list after deletion of node from end -
The node value = 1 and their address = 5508432
The node value = 2 and their address = 5508464
The node value = 3 and their address = 5508480
The node value = 4 and their address = 5508496

Java

/* Java Program To Delete a Node from end in singly linked list */
//Save it as DeleteNodeEndSinglyLinkedList.java

import java.io.*;
import java.util.Scanner;

public class DeleteNodeEndSinglyLinkedList {
	
	// Declaring node
	class Node {
		int data;
		Node next;

		public Node(int data) {
			this.data = data;
			
			// Assigning null value to the next field
			this.next = null;
		}
	}

	public Node head = null;
	
	// Function to add node
	public void addNode(int data) {
		
		// Creating a new node
		Node newNode = new Node(data);
		
		/* If list is empty assign the address of newly created node to head */
		if (head == null) {
			head = newNode;
		} else {
			
			/*
			 * If list already have few elements then loop through list and
			 */
			Node ptr = head;
			while (ptr.next != null) {
				ptr = ptr.next;
			}
			ptr.next = newNode;
		}
	}

	public void display() {
		Node ptr = head;
		
		// If list is empty
		if (ptr == null) {
			System.out.println("The list is empty");
			return;
		}
		System.out.println("The nodes of lists are : ");
		
		/*
		 * If list has elements then loop through the loop and print elements one by one
		 * in sequential manner
		 */
		while (ptr != null) {
			System.out.print(ptr.data + " ");
			ptr = ptr.next;
		}
	}

	public static void main(String[] args) {

		Scanner scanner = new Scanner(System.in);

		DeleteNodeEndSinglyLinkedList list = new DeleteNodeEndSinglyLinkedList();

		System.out.println("Enter number of node you want to enter : ");
		int n = scanner.nextInt();

		for (int i = 0; i < n; i++) {
			System.out.println("Enter value of " + (i + 1) + " node : ");
			int val = scanner.nextInt();
			list.addNode(val);
		}
		
		// Calling function to display list
		list.display();

		list.delete_end();
		
		// Calling function to display list after deletion of a node from end
		System.out.println("\nAfter deletion of a node from end - ");
		list.display();
	}
	
	//Function to delete a node from end
	private void delete_end() {
		Node preptr = null, ptr;
		
		//If list do not have any element, show proper message
		if(head==null) {
			System.out.println("Link list is empty..No node to delete!!");
		}else if(head.next==null) {
			
			//If list have only one element
			ptr=head;
			head=null;
		}else {
			
			//If list have more than one elements
			ptr=head;
			while(ptr.next!=null) {
				preptr=ptr;
				ptr=ptr.next;
			}
			preptr.next=null;
		}
	}
}

Input:
Enter number of node you want to enter : 
5
Enter value of 1 node : 
1
Enter value of 2 node : 
2
Enter value of 3 node : 
3
Enter value of 4 node : 
4
Enter value of 5 node : 
5
The nodes of lists are : 
1 2 3 4 5 

Output:
After deletion of a node from end - 
The nodes of lists are : 
1 2 3 4

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