如何使用算术符号而不是内置的函数？

Question

我正在用python做一个数学测验，并使用3个运算符:加、减和乘。我想使用算术运算符，但我发现它很困难，因为python只是将它作为符号来读取，如果我只打印它。我使用以下代码：

import random
import operator
opslist = [          # This is the bit that I want to change, i also want 
    operator.add,    # the operators all on one line
    operator.sub,
    operator.mul
]

num1 = random.randint(1,10)  # These are two random numbers for my quiz
num2 = random.randint(1,10)
ops = random.choice(opslist) #Random operator for my quiz

total = (ops(num1,num2))    # Answer for my quiz

print (num1,ops,num2)       # Random question for my quiz

这是输出：

6 <built-in function add> 5

1.)如何使输出"6+5“

2.)此外，我如何使这些数字只进行小的计算，得到肯定的答案，这样问题就不会像"5-8“这样的问题。

Answer 1

我也会在你的代码中使用字典。我就是这么做的。

import random
import operator

opslist= {
    operator.add: "+",    # the operators all on one line
    operator.sub: "-",
    operator.mul: "x"
}

num1 = random.randint(1,10)  # These are two random numbers for my quiz
num2 = random.randint(1,10)
ops = random.choice(list(opslist.keys())) #Random operator from opslist keys

total = (ops(num1,num2)) # Answer for my quiz

print(num1,opslist[ops],num2)

当打印问题时，程序会打印出操作员的标志。要确保没有负数，请在“总计”下面添加以下内容：

while total < 0:
    num1 = random.randint(1,10)
    num2 = random.randint(1,10)
    ops = random.choice(opslist)

    total = (ops(num1,num2))

Answer 2

您可以使用字典将操作映射到其符号表示形式。此外，还可以添加一些减法逻辑，以确保num2低于num1

import random
import operator
ops = {
    operator.add: '+', 
    operator.sub: '-',
    operator.mul: '*'
}
num1, num2 = random.randint(1, 10), random.randint(1, 10)
op = random.choice(ops.keys())
if op != operator.sub or num2 <= num1:
    print "%d %s %d = %d" % (num1, ops[op], num2, op(num1, num2))

可能的结果：

3 - 2 = 1