//
// Created by shreenath on 24/7/16.
//
#include <stdio.h>
#include <stdlib.h>

struct node
{
    int data;
    struct node* link;
}*head;

struct node *head=NULL;

void insertFront(int insertData)
{
    struct node *temp=(struct node*)malloc(sizeof(struct node));
    temp->data=insertData;
    temp->link=head->link;
    head=temp;
    printf("\nNode Added at Front : Data = %d",head->data);
}

void insertMiddle(int insertData, int key)
{
    struct node *temp=(struct node*)malloc(sizeof(struct node));
    struct node *pre=(struct node*)malloc(sizeof(struct node));
    temp->data=insertData;
    pre=head;
    while(pre->data!=key)
        pre=pre->link;
    temp->link=pre->link;
    pre->link=temp;
    printf("\nNode Added at Middle : Data = %d",temp->data);
}

void insertLast(int insertData)
{
    struct node *temp=(struct node*)malloc(sizeof(struct node));
    struct node *pre=(struct node*)malloc(sizeof(struct node));
    temp->data=insertData;
    pre=head;
    while(pre->link!=NULL)
        pre=pre->link;
    pre->link=temp;
    temp->link=NULL;
    printf("\nNode Added at Last : Data = %d",temp->data);
}

void traversal()
{
    struct node *pre=(struct node*)malloc(sizeof(struct node));
    int i;i=0;
    pre=head;
    printf("\nLinked List Traversal");
    while(pre->link!=NULL)
    {
        printf("Node %d - %d\n",i,pre->data);
        pre=pre->link;
        i++;
    }
}

void main()
{
    int ch,key;
    int newdata;
    printf("1. Insertion at Front"
                   "\n2. Insertion at Middle"
                   "\n3. Insertion at Last"
                   "\n4. Traversal"
                   "\n5. Exit");
    do
    {
        printf("\nEnter your Choice: ");
        scanf("%d",&ch);
        switch(ch)
        {
            case 1: printf("\nEnter Data: ");
                scanf("%d",&newdata);
                insertFront(newdata);
                break;
            case 2: printf("\nEnter Data and Key: ");
                scanf("%d,%d",&newdata,&key);
                insertMiddle(newdata,key);
                break;
            case 3: printf("\nEnter Data: ");
                scanf("%d",&newdata);
                insertLast(newdata);
                break;
            case 4: traversal();
                break;
            case 5: printf("\nThank You");
                break;
            default: printf("\nInvalid Entry! Re-Enter");
        }
    }while(ch!=5);

}