Queue implementation program

// 4) WAP to implement Queue
#include <iostream>
using namespace std;
const int QueueSpace=10;
int rear=-1;
int front=0;
int Queue[QueueSpace];

void push(int data){
    if(rear==(QueueSpace-1)){
        cout<<"Queue over flowed!!!"<<endl;
        return ;
    }
    Queue[++rear] = data;
}

void pop(){
    if(front==rear+1){
        cout<<"Queue under flowed!!!"<<endl;
        return ;
    }
    front++;
}

void peek(){
    if(front==rear+1){
        cout<<"Queue is empty!!!"<<endl;
        return ;
    }
    cout<<"Current front element of Queue is: "<<Queue[front]<<endl;
}

void size(){
    cout<<"Current Queue size: "<<rear-front+1<<endl;
}

void printQueue(){
    cout<<"Current Queue elements: ";
    for(int i=front;i<=rear;i++){
        cout<<Queue[i]<<" ";
    }
    cout<<endl;
}
int main(){

    push(10);
    push(20);
    push(30);
    push(40);
    peek();
    size();
    printQueue();
    pop();
    peek();
    size();
    printQueue();

    return 0;
}
/*
    OUTPUT:

    Current front element of Queue is: 10
    Current Queue size: 4
    Current Queue elements: 10 20 30 40
    Current front element of Queue is: 20
    Current Queue size: 3
    Current Queue elements: 20 30 40
*/