random

#include<iostream>
using namespace std;

int head = -1 , tail = -1 , array[3] , size = 3; //declare head and tail as -1 and took a array with size 3
//ISFULL
bool isEmpty(){
    if(head == -1 && tail == -1){
        return true;
    } //check the condition is it empty??
    return false;
}

//ISEMPTY
/*bool isFull(){
    if(tail > size - 1){
        return true;
    }//check the condition is it full??
    return false;
}*/
bool isFull(){
    if(tail >= size - 1){
        return true;
    }//check the condition is it full??
    return false;
}

//ENQUEUE
void enqueue(int val){
    head = 0;
    if(isFull() == false){
        tail++;
        array[tail] = val; //store the parameter value into the tail index

    }else{
        cout  << "Array is full" << endl;
    }//check the condition and add a value into the tail section

}


//DEQUEUE
void dequere(){
    if(isEmpty()){
        return;
    }else{
        if(tail == 0 && head == 0){
            head++;//when we use only one data.
        }else{
            array[head];
            head++;
        }
    }//check the condition and remove the head data or first data from the queue
}

//PEEK
int peek(){
    if(!(isEmpty())){
        return  array[head];//return the peek data from the head section.
    }
    return -1;//return -1 if the array is full.
}


//Main function
int main(){
    peek();
    enqueue(100);
    enqueue(200);
    enqueue(300);
    enqueue(300);
    //dequere();

    cout << peek();
}