singly linked list problem

[Hamxa1994]

#include<iostream>
#include<cstdio>
#include<cstdlib>
#include <string>
#include <cstring>
using namespace std;
/*
* Node Declaration
*/
struct node
{
string info;
struct node *next;
}*start;

/*
* Class Declaration
*/
class single_llist
{
public:
node* create_node(string);
void insert_begin();
void insert_pos();
void insert_last();
void delete_pos();
void sort();
void search();
void update();
void reverse();
void display();
single_llist()
{
start = NULL;
}
};

/*
* Main :contains menu
*/
main()
{
int choice, nodes, element, position, i;
single_llist sl;
start = NULL;
while (1)
{
cout<<endl<<"---------------------------------"<<endl;
cout<<endl<<"Operations on singly linked list"<<endl;
cout<<endl<<"---------------------------------"<<endl;
cout<<"1.Insert Node at beginning"<<endl;
cout<<"2.Insert node at last"<<endl;
cout<<"3.Insert node at position"<<endl;
cout<<"4.Sort Link List"<<endl;
cout<<"5.Delete a Particular Node"<<endl;
cout<<"6.Update Node Value"<<endl;
cout<<"7.Search Element"<<endl;
cout<<"8.Display Linked List"<<endl;
cout<<"9.Reverse Linked List "<<endl;
cout<<"10.Exit "<<endl;
cout<<"Enter your choice : ";
cin>>choice;
switch(choice)
{
case 1:
cout<<"Inserting Node at Beginning: "<<endl;
sl.insert_begin();
cout<<endl;
break;
case 2:
cout<<"Inserting Node at Last: "<<endl;
sl.insert_last();
cout<<endl;
break;
case 3:
cout<<"Inserting Node at a given position:"<<endl;
sl.insert_pos();
cout<<endl;
break;
case 4:
cout<<"Sort Link List: "<<endl;
sl.sort();
cout<<endl;
break;
case 5:
cout<<"Delete a particular node: "<<endl;
sl.delete_pos();
break;
case 6:
cout<<"Update Node Value:"<<endl;
sl.update();
cout<<endl;
break;
case 7:
cout<<"Search element in Link List: "<<endl;
sl.search();
cout<<endl;
break;
case 8:
cout<<"Display elements of link list"<<endl;
sl.display();
cout<<endl;
break;
case 9:
cout<<"Reverse elements of Link List"<<endl;
sl.reverse();
cout<<endl;
break;
case 10:
cout<<"Exiting..."<<endl;
exit(1);
break;
default:
cout<<"Wrong choice"<<endl;
}
}
}

/*
* Creating Node
*/
node *single_llist::create_node(string name)
{
struct node *temp, *s;
temp = new(struct node);
if (temp == NULL)
{
cout<<"Memory not allocated "<<endl;
return 0;
}
else
{
temp->info = name;
temp->next = NULL;
return temp;
}
}

/*
* Inserting element in beginning
*/
void single_llist::insert_begin()
{
string name;
cout<<"Enter the name to be inserted: ";
cin>>name;
struct node *temp, *p;
temp = create_node(name);
if (start == NULL)
{
start = temp;
start->next = NULL;
}
else
{
p = start;
start = temp;
start->next = p;
}
cout<<"Element Inserted at beginning"<<endl;
}

/*
* Inserting Node at last
*/
void single_llist::insert_last()
{
string name;
cout<<"Enter the name to be inserted: ";
cin>>name;
struct node *temp, *s;
temp = create_node(name);
s = start;
while (s->next != NULL)
{
s = s->next;
}
temp->next = NULL;
s->next = temp;
cout<<"Element Inserted at last"<<endl;
}

/*
* Insertion of node at a given position
*/
void single_llist::insert_pos()
{
string name;
int pos, counter = 0;
cout<<"Enter the name to be inserted: ";
cin>>name;
struct node *temp, *s, *ptr;
temp = create_node(name);
cout<<"Enter the postion at which node to be inserted: ";
cin>>pos;
int i;
s = start;
while (s != NULL)
{
s = s->next;
counter++;
}
if (pos == 1)
{
if (start == NULL)
{
start = temp;
start->next = NULL;
}
else
{
ptr = start;
start = temp;
start->next = ptr;
}
}
else if (pos > 1 && pos <= counter)
{
s = start;
for (i = 1; i < pos; i++)
{
ptr = s;
s = s->next;
}
ptr->next = temp;
temp->next = s;
}
else
{
cout<<"Positon out of range"<<endl;
}
}

/*
* Sorting Link List
*/
void single_llist::sort()
{
struct node *ptr, *s;
string name;
if (start == NULL)
{
cout<<"The List is empty"<<endl;
return;
}
ptr = start;
while (ptr != NULL)
{
for (s = ptr->next;s !=NULL;s = s->next)
{
if (ptr->info > s->info)
{
name = ptr->info;
ptr->info = s->info;
s->info = name;
}
}
ptr = ptr->next;
}
}

/*
* Delete element at a given position
*/
void single_llist::delete_pos()
{
int pos, i, counter = 0;
if (start == NULL)
{
cout<<"List is empty"<<endl;
return;
}
cout<<"Enter the position of name to be deleted: ";
cin>>pos;
struct node *s, *ptr;
s = start;
if (pos == 1)
{
start = s->next;
}
else
{
while (s != NULL)
{
s = s->next;
counter++;
}
if (pos > 0 && pos <= counter)
{
s = start;
for (i = 1;i < pos;i++)
{
ptr = s;
s = s->next;
}
ptr->next = s->next;
}
else
{
cout<<"Position out of range"<<endl;
}
free(s);
cout<<"Element Deleted"<<endl;
}
}

/*
* Update a given Node
*/
void single_llist::update()
{
string name;
int pos, i;
if (start == NULL)
{
cout<<"List is empty"<<endl;
return;
}
cout<<"Enter the node postion to be updated: ";
cin>>pos;
cout<<"Enter the new name: ";
cin>>name;
struct node *s, *ptr;
s = start;
if (pos == 1)
{
start->info = name;
}
else
{
for (i = 0;i < pos - 1;i++)
{
if (s == NULL)
{
cout<<"There are less than "<<pos<<" elements";
return;
}
s = s->next;
}
s->info = name;
}
cout<<"Node Updated"<<endl;
}

/*
* Searching an element
*/
void single_llist::search()
{
string name;
int pos = 0;
bool flag = false;
if (start == NULL)
{
cout<<"List is empty"<<endl;
return;
}
cout<<"Enter the name to be searched: ";
cin>>name;
struct node *s;
s = start;
while (s != NULL)
{
pos++;
if (s->info == name)
{
flag = true;
cout<<"Element "<<name<<" is found at position "<<pos<<endl;
}
s = s->next;
}
if (!flag)
cout<<"Element "<<name<<" not found in the list"<<endl;
}

/*
* Reverse Link List
*/
void single_llist::reverse()
{
struct node *ptr1, *ptr2, *ptr3;
if (start == NULL)
{
cout<<"List is empty"<<endl;
return;
}
if (start->next == NULL)
{
return;
}
ptr1 = start;
ptr2 = ptr1->next;
ptr3 = ptr2->next;
ptr1->next = NULL;
ptr2->next = ptr1;
while (ptr3 != NULL)
{
ptr1 = ptr2;
ptr2 = ptr3;
ptr3 = ptr3->next;
ptr2->next = ptr1;
}
start = ptr2;
}

/*
* Display Elements of a link list
*/
void single_llist::display()
{
struct node *temp;
if (start == NULL)
{
cout<<"The List is Empty"<<endl;
return;
}
temp = start;
cout<<"Elements of list are: "<<endl;
while (temp != NULL)
{
cout<<temp->info<<"->";
temp = temp->next;
}
cout<<"NULL"<<endl;
}

[Hamxa1994]

here is the question

Use linked list to store employee record. Also implement sorting of employees on the basis of:
a. ID Ascending / Descending order
b. Name Ascending / Descending order
c. Age Ascending / Descending order
i cant seems to add anything except name :(

[gunnerfunner]

struct node
{
    std::string info;
    struct node* next;
}*start;

You need to give struct node the data-members that you wish you add - ID, name, age, etc. Pardon me if I am wrong but it seems the code has originated elsewhere which is fine as long as you can understand and adapt it for your needs

[Hamxa1994]

Thanks man i did some changing ,now my code is complete check it out . Any alternative code would be helpful for my knowledge

http://www.mediafire.com/file/ht2xyfb4cf697yt/New+Text+Document.txt