how to manipluate two lists to make a reciept method-CodePudding

I wanted to make a reciept that prints out in the format names:prices however its seems super hard considering I would have to loop thourugh both lists can someone help me find an solution

class CashRegister:
    def __init__(self,names,prices):
        self._itemCount = 0
        self._totalPrice = 0.0
        self._names = [names]
        self._prices = [prices]

    def addItem(self, names,prices):
        self._names = [names]
        self._prices = [prices]

    def getTotal(self):
        self._totalPrice = sum(self._prices)
        return self._totalPrice
    def getCount(self):
        count = 0
        for i in self._prices:
            count = count   1
        self._itemCount = count


    def clear(self):
        self._itemCount = 0
        self._totalPrice = 0.0
    def updatetax(self,tax):
        if 1 <= tax <= 20:
            self._tax_percent = tax
        else: self._tax_percent = 0

    def get_total_tax(self):
        return self._totalPrice * self._tax_percent
    def reciept(self):
        # use the lists ( name and prices)

CodePudding user response：

Assuming names and prices are the same length:

for pos in range(len(names)):
    print(names[pos], prices[pos])

CodePudding user response：

Since the length of "self._names" is equal to the length of "self._prices", we can use the zip function to get a generator. For example, we can "zip" together these lists to get a list of tuples:

print(list(zip([1, 2, 3], [4, 5, 6])))

We will get the following output:

[(1, 4), (2, 5), (3, 6)]

Using this function, we can write this code:

def reciept(self):
    # zip together the lists and convert generator to list
    zipped_up = list(zip(self._names, self._prices))
    # loop through and print
    for set_of_values in zipped_up:
        print(f"{set_of_values[0]}: {set_of_values[1]}")

Just so you know, in the "init" function, you wrote:

self._names = [names]
self._prices = [prices]

This would have made a list of lists, which you probably didn't want, so instead you could use the asterisk operand to unpack them as:

self._names = [*names]
self._prices = [*prices]