C Program to Implement Single Linked List Operations

#include<stdio.h>
#include<stdlib.h>
struct Node;
typedef struct Node * PtrToNode;
typedef PtrToNode List;
typedef PtrToNode Position;

struct Node
{
    int e;
    Position next;
};

void Insert(int x, List l, Position p)
{
    Position TmpCell;
    TmpCell = (struct Node*) malloc(sizeof(struct Node));
    if(TmpCell == NULL)
        printf("Memory out of space\n");
    else
    {
        TmpCell->e = x;
        TmpCell->next = p->next;
        p->next = TmpCell;
    }
}

int isLast(Position p)
{
    return (p->next == NULL);
}

Position FindPrevious(int x, List l)
{
    Position p = l;
    while(p->next != NULL && p->next->e != x)
        p = p->next;
    return p;
}

void Delete(int x, List l)
{
    Position p, TmpCell;
    p = FindPrevious(x, l);

    if(!isLast(p))
    {
        TmpCell = p->next;
        p->next = TmpCell->next;
        free(TmpCell);
    }
    else
        printf("Element does not exist!!!\n");
}

void Display(List l)
{
    printf("The list element are :: ");
    Position p = l->next;
    while(p != NULL)
    {
        printf("%d -> ", p->e);
        p = p->next;
    }
}

void Merge(List l, List l1)
{
    int i, n, x, j;
    Position p;
    printf("Enter the number of elements to be merged :: ");
    scanf("%d",&n);

    for(i = 1; i <= n; i++)
    {
        p = l1;
        scanf("%d", &x);
        for(j = 1; j < i; j++)
            p = p->next;
        Insert(x, l1, p);
    }
    printf("The new List :: ");
    Display(l1);
    printf("The merged List ::");
    p = l;
    while(p->next != NULL)
    {
        p = p->next;
    }
    p->next = l1->next;
    Display(l);
}


int main()
{
    int x, pos, ch, i;
    List l, l1;
    l = (struct Node *) malloc(sizeof(struct Node));
    l->next = NULL;
    List p = l;
    printf("LINKED LIST IMPLEMENTATION OF LIST ADT\n\n");
    do
    {
        printf("\n\n1. INSERT\t 2. DELETE\t 3. MERGE\t 4. PRINT\t 5. QUIT\n\nEnter the choice :: ");
        scanf("%d", &ch);
        switch(ch)
        {
        case 1:
            p = l;
            printf("Enter the element to be inserted :: ");
            scanf("%d",&x);
            printf("Enter the position of the element :: ");
            scanf("%d",&pos);

            for(i = 1; i < pos; i++)
            {
                p = p->next;
            }
            Insert(x,l,p);
            break;

        case 2:
            p = l;
            printf("Enter the element to be deleted :: ");
            scanf("%d",&x);
            Delete(x,p);
            break;

        case 3:
            l1 = (struct Node *) malloc(sizeof(struct Node));
            l1->next = NULL;
            Merge(l, l1);
            break;

        case 4:
            Display(l);
            break;
        }
    }
    while(ch<5);
    return 0;
}

OUTPUT:

LINKED LIST IMPLEMENTATION OF LIST ADT



1. INSERT        2. DELETE       3. MERGE        4. PRINT        5. QUIT

Enter the choice :: 1
Enter the element to be inserted :: 10
Enter the position of the element :: 1


1. INSERT        2. DELETE       3. MERGE        4. PRINT        5. QUIT

Enter the choice :: 1
Enter the element to be inserted :: 20
Enter the position of the element :: 2


1. INSERT        2. DELETE       3. MERGE        4. PRINT        5. QUIT

Enter the choice :: 1
Enter the element to be inserted :: 30
Enter the position of the element :: 3


1. INSERT        2. DELETE       3. MERGE        4. PRINT        5. QUIT

Enter the choice :: 4
The list element are :: 10 -> 20 -> 30 ->

1. INSERT        2. DELETE       3. MERGE        4. PRINT        5. QUIT

Enter the choice :: 5