昂贵的计算程序操作数混乱

问题描述

我想要做的是让初始输入取一个数字，然后继续取之后输入的数字，直到通过输入 0 关闭循环。输出应该是初始输入，输入的数量相加，然后从初始数字中减去。

我想尽可能少地改变程序的整体结构。

budget = float(input('Enter amount budgeted for the month: '))
spent = 0
total = 0
while spent >= 0:
    spent = float(input('Enter an amount spent(0 to quit): '))
    total += spent
    print ('Budgeted: $',format(budget,'.2f'))
    print ('Spent: $',format(total,'.2f'))
    if budget > total:
        difference = budget - total
        print ('You are $',format(difference,'.2f'),\
            'under budget. WELL DONE!')
    elif budget < total:
        difference = total - budget
        print ('You are $',\
           'over budget. PLAN BETTER NEXT TIME!')
    elif budget == total:
        print ('Spending matches budget. GOOD PLANNING!')

解决方法

首先，您需要循环直到用户输入 0。您可以使用在 0 处中断的循环：

while True:
    spent = float(input('Enter an amount spent(0 to quit): '))
    if spent == 0: break
    total += spent

或循环直到 spent 为 0。这意味着将其初始化为某个非零值。

spent = -1
while spent != 0:
    spent = float(input('Enter an amount spent(0 to quit): '))
    total += spent

此外，所有其他代码都应该在循环之外：

budget = float(input('Enter amount budgeted for the month: '))
spent = -1
total = 0
while spent != 0:
    spent = float(input('Enter an amount spent(0 to quit): '))
    total += spent
print ('Budgeted: $',format(budget,'.2f'))
print ('Spent: $',format(total,'.2f'))
if budget > total:
    difference = budget - total
    print ('You are $',format(difference,'.2f'),\
                'under budget. WELL DONE!')
elif budget < total:
    difference = total - budget
    print ('You are $',\
               'over budget. PLAN BETTER NEXT TIME!')
else:
    print ('Spending matches budget. GOOD PLANNING!')