C++ Programming Code Examples
C++ > Data Structures Code Examples
C++ Program to Implement Queue using Linked List
/* C++ Program to Implement Queue using Linked List
This C++ program, using iteration, implements the list of elements removed from the queue in first in first out mode using a linked list. A linked list is an ordered set of data elements, each containing a link to its successor. */
#include<iostream>
#include<stdio.h>
#include<conio.h>
using namespace std;
struct node
{
int data;
node *next;
}*front = NULL,*rear = NULL,*p = NULL,*np = NULL;
void push(int x)
{
np = new node;
np->data = x;
np->next = NULL;
if(front == NULL)
{
front = rear = np;
rear->next = NULL;
}
else
{
rear->next = np;
rear = np;
rear->next = NULL;
}
}
int remove()
{
int x;
if(front == NULL)
{
cout<<"empty queue\n";
}
else
{
p = front;
x = p->data;
front = front->next;
delete(p);
return(x);
}
}
int main()
{
int n,c = 0,x;
cout<<"Enter the number of values to be pushed into queue\n";
cin>>n;
while (c < n)
{
cout<<"Enter the value to be entered into queue\n";
cin>>x;
push(x);
c++;
}
cout<<"\n\nRemoved Values\n\n";
while(true)
{
if (front != NULL)
cout<<remove()<<endl;
else
break;
}
getch();
}
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