Notes

Q.3 Write a menu driven program that maintains a linear linked list whose element are stored in an ascending order and implements the following operation a) create list b) display the list c) Search an element.
PROGRAM
#include<iostream>
using namespace std;
struct node
{
int info;
struct node *next;
}*start;
class single_llist
{
public:
node* create_node(int);
void insert();
void search();
void display();
single_llist()
{
start = NULL;
}
};
main()
{
int choice, nodes, element, position, i;
single_llist sl;
start = NULL;

while (1)
{
cout<<"1.Insert Node at beginning"<<endl;
cout<<"2.Search Element"<<endl;
cout<<"3.Display Linked List"<<endl;
cout<<"4.Exit "<<endl;
cout<<"Enter your choice : ";
cin>>choice;
switch(choice)
{
case 1:
cout<<"Inserting Node : "<<endl;
sl.insert();
cout<<endl;
break;
case 2:
cout<<"Search element in Link List: "<<endl;
sl.search();
cout<<endl;
break;
case 3:
cout<<"Display elements of link list"<<endl;
sl.display();
cout<<endl;
break;
case 4:
cout<<"Exiting..."<<endl;
exit(1);
break;
default:
cout<<"Wrong choice"<<endl;
}
}
}
node *single_llist::create_node(int value)
{
struct node *temp, *s;
temp = new(struct node);
if (temp == NULL)
{
cout<<"Memory not allocated "<<endl;
return 0;
}
else
{
temp->info = value;
temp->next = NULL;
return temp;
}
}
void single_llist::insert()
{
int value;
cout<<"Enter the value to be inserted: ";
cin>>value;
struct node *temp, *p;
temp = create_node(value);
if (start == NULL)
{
start = temp;
start->next = NULL;
}
else
{
p = start;
start = temp;
start->next = p;
}
cout<<"Element Inserted "<<endl;
}
void single_llist::search()
{
int value, pos = 0;
if (start == NULL)
{
cout<<"List is empty"<<endl;
return;
}
cout<<"Enter the value to be searched: ";
cin>>value;
struct node *s;
s = start;
while (s != NULL)
{
pos++;
if (s->info == value)
{
cout<<"Element "<<value<<" is found at position "<<pos<<endl;
}
s = s->next;
}

}

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;
}




OUTPUT