IMPLEMENT THE addItem() and printReceipt() functions only in C++. (you can add helper functions/variables if needed)

// You are working in a company that writes software to run on supermarket checkout systems. This is the interface of one of the components in the system:

class ShoppingCart {

/*

called every time the cashier swipes a new item

barcodeString: string output of a barcode scanner

number: number of instances of this item being added

*/

void addItem(string barcodeString, int number){

}

// outputs a formatted receipt to stdout.

void printReceipt();

}

/*

The expected format of the receipt is:

Item Unit price Quantity Total

Pear $1.20 2 $2.40

Apple $0.30 3 $0.90

Total: $3.30

focus on code quality, maintainability, and testability.