Linked Lists

Menu Driven Program For All Operations

#include <stdio.h>
#include <iostream>
#include <limits.h>
#include <stdlib.h>
#include <bits/stdc++.h>
using namespace std;

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

struct header
{
    float avg;
    int max1,min1,max2,min2,totalnode;
    struct node *next;
};

void headerfunc(struct header *);
void insertf(struct header *);
void deletef(struct header *);
void bubble_sort(struct header *);
void display(struct header *);
void avg(struct header *);
void max_min(struct header *);
void max2_min2(struct header *);
void disp_odd(struct header *);
void disp_even(struct header *);
struct node * new_node(int data);

int main(void)
{
    struct header *head=new header;
    head->avg=0;
    head->max1=0;
    head->max2=0;
    head->min1=0;
    head->min2=0;
    head->totalnode=0;
    head->next=NULL;
    int c=0;
    while(true)
    {
        cout<<"\n\nPress 1 to insert in Linked list";
        cout<<"\nPress 2 to delete in Linked list";
        cout<<"\nPress 3 for sorting the Linked list(Bubble Sort)";
        cout<<"\nPress 4 to display the Linked list";
        cout<<"\nPress 5 to show the average of the Linked list";
        cout<<"\nPress 6 to show the maximum and minimum element of the Linked list";
        cout<<"\nPress 7 to to show the second maximum and second minimum element of the Linked list";
        cout<<"\nPress 8 to show the odd node elements";
        cout<<"\nPress 9 to show the even node elements";
        cout<<"\nPress 0 to exit : ";
        cin>>c;
        cout<<"\n";
        switch(c)
        {
            case 0:
                    exit(0);
            case 1: insertf(head);
                    break;
            case 2: deletef(head);
                    break;
            case 3: bubble_sort(head);
                    break;
            case 4: display(head);
                    break;
            case 5: cout<<"\nAverage of Linked List is : "<<head->avg;
                    break;
            case 6: cout<<"\nMaximum element of Linked List is : "<<head->max1;
                    cout<<"\nMinimum element of Linked List is : "<<head->min1;
                    break;
            case 7: cout<<"\nSecond maximum element of Linked List is : "<<head->max2;
                    cout<<"\nSecond minimum element of Linked List is : "<<head->min2;
                    break;
            case 8: disp_odd(head);
                    break;
            case 9: disp_even(head);
                    break;
            default:cout<<"\n****Wrong input****";
                    cout<<"\n    Enter again\n";
        }
    }
    return 0;
}

struct node * new_node(int data)
{
    struct node *nnd=new node;
    nnd->data=data;
    nnd->next=NULL;
    return nnd;
}

void headerfunc(struct header * head)
{
    struct node * ptr=head->next;
    int i=0;
    while(ptr!=NULL)
    {
        ++i;
        ptr=ptr->next;
    }
    head->totalnode=i;
    avg(head);
    max_min(head);
    max2_min2(head);
}

void insertf(struct header *  head)
{
    int ins=0;
    cout<<"\nInsertion in the end.";
    cout<<"\nEnter element to be inserted(-1 to exit) : ";
    cin>>ins;
    while(ins!=-1)
    {
        struct node *nnd=new_node(ins);
        if(head->next==NULL)
            head->next=nnd;
        else
        {
            struct node *ptr=head->next;
            while(ptr->next!=NULL)
                ptr=ptr->next;
            ptr->next=nnd;
        }
        cout<<"\nEnter element to be inserted(-1 to exit) : ";
        cin>>ins;
    }
    headerfunc(head);
    display(head);
}

void deletef(struct header * head)
{
    struct node *ptr=head->next,*preptr=head->next;
    int del=0;
    cout<<"\nEnter element to be deleted : ";
    cin>>del;
    while(ptr->data!=del)
    {
        preptr=ptr;
        ptr=ptr->next;
    }
    preptr->next=ptr->next;
    delete ptr;
    headerfunc(head);
    display(head);
}

void bubble_sort(struct header * head)
{
    struct node * ptr=head->next;
    int ar[head->totalnode],i=0;
    while(ptr!=NULL)
    {
        ar[i]=ptr->data;
        ++i;
        ptr=ptr->next;
    }
    sort(ar,ar+head->totalnode);
    ptr=head->next;
    i=0;
    while(ptr!=NULL)
    {
        ptr->data=ar[i];
        ++i;
        ptr=ptr->next;
    }
    cout<<"\nSorted Linked List is :\n";
    display(head);
}

void display(struct header * head)
{
    struct node * ptr=head->next;
    cout<<"\nLinked List is : ";
    while(ptr!=NULL)
    {
        cout<<ptr->data<<" ";
        ptr=ptr->next;
    }
}

void avg(struct header * head)
{
    int sum=0;
    struct node * ptr=head->next;
    while(ptr!=NULL)
    {
        sum=sum+ptr->data;
        ptr=ptr->next;
    }
    head->avg=(float)sum/(head->totalnode);
}

void max_min(struct header * head)
{
    struct node * ptr=head->next;
    int max1=0,min1=0;
    max1=INT_MIN;
    min1=INT_MAX;
    while(ptr!=NULL)
    {
        if(max1<ptr->data)
            max1=ptr->data;
        if(min1>ptr->data)
            min1=ptr->data;
        ptr=ptr->next;
    }
    head->max1=max1;
    head->min1=min1;
}

void max2_min2(struct header * head)
{
    struct node * ptr=head->next;
    int min2=INT_MAX,max2=INT_MIN;
    while(ptr!=NULL)
    {
        if(max2<ptr->data&&ptr->data!=head->max1)
            max2=ptr->data;
        if(min2>ptr->data&&ptr->data!=head->min1)
            min2=ptr->data;
        ptr=ptr->next;
    }
    head->max2=max2;
    head->min2=min2;
}

void disp_odd(struct header * head)
{
    struct node * ptr=head->next;
    cout<<"\nElements at Odd position of Linked List are : ";
    while(ptr!=NULL)
    {
        cout<<ptr->data<<" ";
        if(ptr->next==NULL)
            ptr=ptr->next;
        else
            ptr=ptr->next->next;
    }
}

void disp_even(struct header * head)
{
    struct node * ptr=head->next->next;
    cout<<"\nElements at Even position of Linked List are : ";
    while(ptr!=NULL)
    {
        cout<<ptr->data<<" ";
        if(ptr->next==NULL)
            ptr=ptr->next;
        else
            ptr=ptr->next->next;
    }
}