lab14(queue_usingLL).c

#include<stdio.h>
#include<stdlib.h>
#define MAX_SIZE 3
struct node
{
    int data;
    struct node *next;
}*newnode,*front,*rear,*temp;
int count = 0;
void enQueue(int a){
    newnode = (struct node *)malloc(sizeof(struct node));
    newnode->data = a;
    if (count == MAX_SIZE)           //checking the full condition
    {
        printf("queue full..");
    }
    else if (front == NULL)
    {
       front = newnode;
       rear = newnode;
       newnode->next = NULL;
       count++;                //to check whether the stack has reached to the MAX_SIZE
       printf("node enQueued successfully..");
    }
    else{
        newnode->next = front;
        front = newnode; 
        count++;
        printf("node enQueued successfully..");
    }
}
void deQueue(){
    if (front == NULL)
    {
        printf("nothing here to delete...");
    }
    
    temp = front;
    if (front == rear)
    {
        front = NULL;
        rear = NULL;
    }
    
    while (temp->next != rear)
    {
        temp = temp->next;
    }
    temp->next = NULL;
    free(rear);
    rear =  temp;
    printf("node deQueued succesfully");
}
void traverse(){
    if (front == NULL)
    {
        printf("nothing here to display..");
    }
    else{
        temp = front;
        while (temp->next!=NULL)
        {
            printf("%d -> ",temp->data);
            temp = temp->next;
        }
        printf("%d",temp->data);
    }
}
void main(){
    int ch,data;
     do{
    printf("\n1.enQueue\n2.deQueue\n3.Traverse\n");
    scanf("%d",&ch);
        switch (ch)
        {
        case 1:
            printf("enter the number : ");
            scanf("%d",&data);
            enQueue(data);
            break;
        case 2:
            deQueue();
            break;
        case 3:
            
            traverse();
            break;
        default:
            break;
        }
        printf("\ndo you want to continue (0/1) : ");
        scanf("%d",&ch);
    }while(ch!=0);
}