Queue Data Structure in C++ Programming (using arrays) | All Queue Operations | Part – 2

int count()
{
if(rear==-1 && front==-1)
return 0;
else
return rear-front+1;
}
count should be like this otherwise without element also count will be 1.
Well thank you sir

Nice code but if someone insert 0 in the queue and display it then the output will be just zeros and it may become confusing at that index whether element is inserted or is it empty position. While displaying 0 should be converted to null.

can you pls explain how to enter size of array dynamically instead of already keeping it as 5??

So, I had a quick question. When is a queue full? I understood all the concepts and your video was AWESOME (as always haha)… but not being able to define if the queue was full or not made me think what a queue being full meant? I'd appreciate if you could let me know. Thanks and like you always say… Peace <3

There is mistake in count function also…if we does not enqueue any value….count must be 0 but this will show 1 because in that case rear and front both are -1 and -1-1+1 is 1…..so put this case also in count function when front and rear are -1

#include<iostream>
using namespace std;
class queue{
int i,arr[5],rear,front;
public:
queue(){
rear=0;
front=-1;
for(i=0;i<5;i++)
arr[i]=0;
}
bool isempty(){
if(rear=-1&&front==-1)
return true;
else
return false;
}
bool isfull(){
if(rear==4)
return true;
else
return false;
}
void enque(int value){
if(isfull()){
cout<<"queue is full ,element can't be enque"<<endl;
}
else if(isempty()){
front=0;
rear=0;
arr[rear]=value;
}
else{rear++;
arr[rear]=value;
}}
void deque(){
if(isempty())
{cout<<"queue is empty ,element can't be deque"<<endl;}
else if(rear==front){
arr[front]=0;
front=rear=-1;
}
else
{
arr[front]=0;
front++;
}}
void display(){
for(i=0;i<=4;i++)
cout<<arr[i]<<" ";
}
void peek(int position){
if(rear-front+1>=position)
cout<<arr[position];
else
cout<<"invalid position"<<endl;
}
void change(int position,int value){
if(rear-front+1>=position)
arr[position]=value;
else
cout<<"invalid position";
}
int count(){
return rear-front+1;
}
void ree(){
cout<<rear<<endl;
}
};
int main(){
queue q1;
int value,option,position;
do{
cout<<endl<<"SELECT THE OPERATION,press '0' for stop"<<endl;
cout<<"'1'isEmpty"<<endl;
cout<<"'2'isfull"<<endl;
cout<<"'3'Enque"<<endl;
cout<<"'4'Deque"<<endl;
cout<<"'5'Display"<<endl;
cout<<"'6'peek"<<endl;
cout<<"'7'change"<<endl;
cout<<"'8'Count"<<endl;
cout<<"'9'ClearScreen"<<endl;
cin>>option;
cout<<endl;
switch(option){
case 0: exit(0);
break;
case 1:{if(q1.isempty())
cout<<"queue is empty"<<endl;
else
cout<<"queue is not empty"<<endl;
}
break;
case 2:{if(q1.isfull())
cout<<"queue is full"<<endl;
else
cout<<"queue is not full"<<endl;
}
break;
case 3:{cout<<"enque is called,value:";
cin>>value;
q1.enque(value);
}
break;
case 4: q1.deque();
break;
case 5:q1.display();
break;
case 6:{cout<<"peek option is called, position:";
cin>>position;
q1.peek(position);
}
break;
case 7:{cout<<"change option is callednposition:";
cin>>position;
cout<<"value:";
cin>>value;
q1.change(position,value);
}
break;
case 8:{cout<<"the total no. of elements isn array:"<<q1.count()<<endl;
}
break;
case 9:{system("cls");
}
case 11:{
cout<<"rear=";
q1.ree();}
break;
default:cout<<"enter the proper option"<<endl;
}
}while(option!=0);
}//bro please help me to correct this code ,it is not storing more then two elements, if you enter third element for enque then it will replace third element with second element,

Best explanation but in the count function it is (rear – front +1 ) but if both the rear and count are at -1 and -1 the count should be zero but it is 1..

You are awesome😇

bhai, apke is channel ko to 1Milllion subcribers hona chaiye, itne acche aur satik tareeke se koi DS padha v skta h, vishwas nhi ho rha h!!!!!!!!…m apka bhot bhot abhari hu, jo apne itne jatil vishayon ko v itne saral aur graphics se zariye itna accha banaya ki hm ubte tk nhi!!!!!please ap CS k baaki subjects ko v graphics k zariye padhaeyega (but free m, bhai :)), taki humara bhala ho….apko ishwar sada sukhi rakhe……
-Apka ek subscriber….

Your channel is like finding an oasis in Sahara Desert….. Thanks for the great explanation and endless effort !!!

count shows 1, when queue is empty
how can I solve that??

Bro your way of speaking and fluency in English is wonderful…👍👌👏👏

Sir ,
according to my your function to check whether queue is full or not is wrong
it should be
bool isFull()
{
if(rear- front == 4)
return true;
else
return false;
}

please tell me if i am wrong…….

how download this

When we dequeue all the elements how the rear and front go to -1 as there is no change in rear in the else part of the dequeue function. Whenever i dequeue all the elements i can not enter new elements in the queue so the queue becomes useless. Can you help me?

Awesome!!!! Understood everything..
Thanks.

Today my search ends here about QUEUE…
best explanation…
!!! thanks !!!

Man; this is the best explanation I have ever heard in a YouTube video

even if the queue is empty, the COUNT shows 1.
Please correct that exception.
.
.
Good work man!