#include <stdio.h>
#include <stdlib.h>
 
// Structure for a node
struct Node {
    int data;
    struct Node *next;
};
 
// Function to create linked list
struct Node* createList(int n) {
    struct Node *head = NULL, *temp, *newNode;
    int data, i;
 
    for (i = 1; i <= n; i++) {
        newNode = (struct Node*)malloc(sizeof(struct Node));
        if (newNode == NULL) {
            printf("Memory allocation failed!\n");
            exit(0);
        }
 
        printf("Enter data for node %d: ", i);
        scanf("%d", &data);
        newNode->data = data;
        newNode->next = NULL;
 
        if (head == NULL)
            head = newNode;
        else
            temp->next = newNode;
 
        temp = newNode;
    }
    return head;
}
 
// Function to display linked list
void displayList(struct Node *head) {
    struct Node *temp = head;
    if (head == NULL) {
        printf("\nList is empty.\n");
        return;
    }
    printf("\nLinked List: ");
    while (temp != NULL) {
        printf("%d -> ", temp->data);
        temp = temp->next;
    }
    printf("NULL\n");
}
 
// Function to delete node by value
struct Node* deleteByValue(struct Node *head, int value) {
    struct Node *temp = head, *prev = NULL;
 
    // Case 1: List is empty
    if (head == NULL) {
        printf("\nList is empty. Nothing to delete.\n");
        return NULL;
    }
 
    // Case 2: Value found at head
    if (temp != NULL && temp->data == value) {
        head = temp->next;
        free(temp);
        printf("\nNode with value %d deleted (from beginning).\n", value);
        return head;
    }
 
    // Case 3: Traverse to find value
    while (temp != NULL && temp->data != value) {
        prev = temp;
        temp = temp->next;
    }
 
    // Value not found
    if (temp == NULL) {
        printf("\nValue %d not found in the list.\n", value);
        return head;
    }
 
    // Delete node
    prev->next = temp->next;
    free(temp);
 
    printf("\nNode with value %d deleted successfully.\n", value);
    return head;
}
 
int main() {
    struct Node *head = NULL;
    int n, value;
 
    printf("Enter number of nodes: ");
    scanf("%d", &n);
 
    head = createList(n);
 
    printf("\nBefore deletion:");
    displayList(head);
 
    printf("\nEnter the value to delete: ");
    scanf("%d", &value);
 
    head = deleteByValue(head, value);
 
    printf("\nAfter deletion:");
    displayList(head);
 
    return 0;
}