Locationwise_Linked_List

#include <cstdio>
#include <cstdlib>

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

int count() {
    int c = 0;
    for (Node *Current = Head; Current != NULL; Current = Current -> next)
        c++;
    return c;
}

int display() {
    if (Head == NULL)
        printf("List is Empty");
    for (Node *Current = Head; Current != NULL; Current = Current -> next)
        printf("%d ", Current -> data);
    printf("\n\n");
}

void add(int num) {
    Node *NewNode = (Node *) malloc(sizeof(Node));
    NewNode -> data = num;
    NewNode -> next = NULL;
    if (Head != NULL)
        NewNode -> next = Head;
    Head = NewNode;
}

void addAfter(int num, int loc) {
    int i;
    Node *left, *right, *NewNode;
    right = Head;
    for (i = 0; i < loc; i++) {
        left = right;
        right = right -> next;
    }
    NewNode = (Node *) malloc(sizeof(Node));
    NewNode -> data = num;
    left -> next = NewNode;
    NewNode -> next = right;
}

void append(int num) {
    Node *NewNode = (Node *) malloc(sizeof(Node));
    NewNode -> data = num;
    NewNode -> next = NULL;
    Node *Current = Head;
    while (Current -> next != NULL)
        Current = Current -> next;
    Current -> next = NewNode;
}

void insert(int num) {
    int loc;
    int c = count();
    while (1) {
        printf("Enter the Location: ");
        scanf("%d", &loc);
        if (loc > c || loc < 0)
            printf("Invalid Location.\nMaximum Available Location is: %d\n\n", c);
        else
            break;
    }
    if (loc == 0)
        add(num);
    else if (loc < count())
        addAfter(num, loc);
    else
        append(num);
}

int Delete(int num) {
    for (Node *Current = Head, *Previous; Current != NULL; Previous = Current, Current = Current -> next) {
        if (Current -> data == num) {
            if (Current == Head)
                Head = Head -> next;
            else
                Previous -> next = Current -> next;
            free(Current);
            return 1;
        }
    }
    return 0;
}

int main() {
    int choice, num;
    Head = NULL;

    while (1) {
        printf("List Operations: \n");
        printf("================\n");
        printf("1. Add\n");
        printf("2. Display\n");
        printf("3. Delete\n");
        printf("4. Size\n");
        printf("5. Exit\n");
        printf("Choice: ");
        scanf("%d", &choice);

        switch (choice) {
            case 1: {
                printf("Enter the Number to Add: ");
                scanf("%d", &num);
                insert(num);
                break;
            }
            case 2: {
                display();
                break;
            }
            case 3: {
                if (Head == NULL)
                    printf("List is Empty. Nothing to Delete.\n");
                else {
                    printf("Enter Number to Delete: ");
                    scanf("%d", &num);
                    if (Delete(num) == 1)
                        printf("Successfully Deleted %d\n", num);
                    else
                        printf("%d Not Deleted.\nValue Might Not Found\n", num);
                }
                break;
            }
            case 4: {
                printf("Size of The list is %d\n", count());
                break;
            }
            case 5: {
                exit(0);
            }
            default: {
                printf("Invalid Input. Try Again\n");
            }
        }
        printf("\n\n");
    }
    return 0;
}