QUEUE IMPLEMENTATION USING TEMPLATES

QUEUE IMPLEMENTATION USING TEMPLATES

The following code explains the concept:

        #include<iostream.h>

#include<conio.h>

#define MAX 10

// Create a generic Queue class

template <class Type>

class Queue

{

Type Que[MAX];

int front,rear;

public:

void init()

{

front=rear=-1;

}

void insert(Type ch);

Type delet();

};

/*

---------------------------------------------------------------

insert function

---------------------------------------------------------------

*/

template <class Type>void Queue<Type>::insert(Type item)

{

if (rear>=MAX)

{

cout << "Queue is full\n";

return;

}

if(front==-1)

front++;

Que[++rear] = item;//inserting the item in the Que

}

/*

---------------------------------------------------------------

delet function

---------------------------------------------------------------

*/

template <class Type>Type Queue<Type>::delet()

{

Type val;

if((front==-1)||(front>rear))

{

cout << "Queue is empty\n";

return 0; // return null on empty stack

}

val= Que[front];//item to be deleted

front++;

return val;

}

/*

------------------------------------------------------------

The main function

------------------------------------------------------------

*/

void main()

{

Queue <char> Q1;

Queue <int> Q2;

int i;  

//clrscr();

Q1.init();

Q2.init();

Q1.insert('p');

Q1.insert('q');

Q1.insert('r');

Q2.insert(10);

Q2.insert(20);

Q2.insert(30);

cout << "Delete from Queue of characters: "<<endl;

for (i=0; i<3; i++)

cout<<"  "<<Q1.delet() << "\n";

cout << "Delete from Queue of integers: "<<endl;

for (i=0; i<3; i++)

cout<<"  "<<Q2.delet() << "\n";

// demonstrate double queue

Queue <double> Q3;

Q3.init();

Q3.insert(1.1);

Q3.insert(1.2);

cout << "Delete from Queue of doubles: "<<endl;

for (i=0; i<2; i++)

cout<<"  "<<Q3.delet() << "\n";

getch();

}

If you have any doubt,please feel free to ask.Take care.Good day.