TheAlgorithms-C-Plus-Plus/data_structure/Queue Using Linked List.cpp
2019-11-28 13:28:41 +01:00

90 lines
1.3 KiB
C++

#include <iostream>
using namespace std;
struct node
{
int val;
node *next;
};
node *front, *rear;
void Enque(int x)
{
if (rear == NULL)
{
node *n = new node;
n->val = x;
n->next = NULL;
rear = n;
front = n;
}
else
{
node *n = new node;
n->val = x;
n->next = NULL;
rear->next = n;
rear = n;
}
}
void Deque()
{
if (rear == NULL && front == NULL)
{
cout << "\nUnderflow";
}
else
{
node *t = front;
cout << "\n"
<< t->val << " deleted";
front = front->next;
delete t;
if (front == NULL)
rear = NULL;
}
}
void show()
{
node *t = front;
while (t != NULL)
{
cout << t->val << "\t";
t = t->next;
}
}
int main()
{
int ch, x;
do
{
cout << "\n1. Enque";
cout << "\n2. Deque";
cout << "\n3. Print";
cout << "\nEnter Your Choice : ";
cin >> ch;
if (ch == 1)
{
cout << "\nInsert : ";
cin >> x;
Enque(x);
}
else if (ch == 2)
{
Deque();
}
else if (ch == 3)
{
show();
}
} while (ch != 0);
return 0;
}