购物车

li1 = []
li2 = ['手机','电脑','鼠标垫','游艇']
li = [{'手机':4000,},{'电脑':5000,},{'鼠标垫':100,},{'游艇':10000}]
flag = True
yue = int(input('请输入您的余额'))
while flag:
    for i in li:
         print('{}	{}'.format(li.index(i)+1,i))
    num = input('请输入商品序号/输入Q或q退出：')
    if num.isdigit():
        num = int(num)
        if num > 0 and num <= len (li):
            yue = yue - int(li[num-1].get(li2[num-1]))
            if yue >= 0:
                print('您的余额为',yue)
                li1.append(li[num - 1])
            else:
                print('您的余额不足')
        else:
            print('请输入正确的数字')
    elif num.upper() == 'Q':
        for a in li1:
            for k,v in a.items():
                print(k,v)
        break
    else:
        print('请输入数字')

输入余额，输出商品列表，输入序号选择商品，同时显示所剩余额，若余额不足则提示，退出循环后返回购物车的内容，包括商品和价格