Implementation of Queue in C.

Here is the code..

/*

  AIM :TO PERFORM OPERATIONS ON SIMPLE QUEUE */

#include<stdio.h>

#include<stdlib.h>

#define m 10

int a[m],b[m/2],front=-1,rear=-1,i=0;

void insert();

void del();

void traverse();

void main()

{int c;

clrscr();

printf("1:INSERTION\t2:DELETION\t3:TRAVERSAL\n");

printf("4:EXIT\n");

while(1)

{printf("Enter your choice\t");

scanf("%d",&c);

switch(c)

{

case 1: insert();

break;

case 2: del();

break;

case 3: traverse();

break;

case 4: 

exit(1);

break;

default:printf("TRY AGAIN\n");

break;

}

}

}

void insert()

{int item;

if(rear==(m-1))

{printf("Overflow can not insert\n");

return;

}

if(front==-1 && rear==-1)

front=0;

rear=rear+1;

printf("Enter the value to insert\t");

scanf("%d",&item);

a[rear]=item;

}

void del()

{if(front==-1&&rear==-1)

{printf("Underflow Queue is empty\n");

return;

}

b[i]=a[front];

i++;

a[front]=0;

if(rear==front)

rear=front=-1;

else

front++;

printf("Item deleted\t%d\n",b[i-1]);

}

void traverse()

{int j;

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

{printf("Queue is empty\n");

return;

}

for(j=front;j<=rear;j++)

printf("%d\t",a[j]);

printf("\n");

}

For Turbo C users.

/*

  AIM :TO PERFORM OPERATIONS ON SIMPLE QUEUE */

#include<stdio.h>

#include<conio.h>

#include<stdlib.h>

#define m 10

int a[m],b[m/2],front=-1,rear=-1,i=0;

void insert();

void del();

void traverse();

void main()

{int c;

clrscr();

printf("1:INSERTION\t2:DELETION\t3:TRAVERSAL\n");

printf("4:EXIT\n");

while(1)

{printf("Enter your choice\t");

scanf("%d",&c);

switch(c)

{

case 1: insert();

break;

case 2: del();

break;

case 3: traverse();

break;

case 4: getch();

exit(1);

break;

default:printf("TRY AGAIN\n");

break;

}

}

}

void insert()

{int item;

if(rear==(m-1))

{printf("Overflow can not insert\n");

return;

}

if(front==-1 && rear==-1)

front=0;

rear=rear+1;

printf("Enter the value to insert\t");

scanf("%d",&item);

a[rear]=item;

}

void del()

{if(front==-1&&rear==-1)

{printf("Underflow Queue is empty\n");

return;

}

b[i]=a[front];

i++;

a[front]=0;

if(rear==front)

rear=front=-1;

else

front++;

printf("Item deleted\t%d\n",b[i-1]);

}

void traverse()

{int j;

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

{printf("Queue is empty\n");

return;

}

for(j=front;j<=rear;j++)

printf("%d\t",a[j]);

printf("\n");

}