Question

我的计算机科学课正在做一个练习编程任务，我们需要创建一个程序，询问十个随机问题来测试学生的算术技巧。我为每个问题中的两个数字制作了单独的变量，并为随机操作制作了一个变量。这是我的代码，我正在使用python 3.5，我一直在收到错误。任何人都可以看到我哪里出错...我认为这是使用eval模块。

    #This is where the import commands go
from random import randint
import random




#This is a set list of variables for each question (21 in total as 2 for each question and operation)

operation = ['x', '-', '+']
q1p1 = (randint(0,100))
q1p2 = (randint(0,100))


#This variable stores the users score
score = 0


#This changes the randomly generated numbers into strings, then evauates them as maths equations so it knows the answers.
#Also it stores the whole of each question as a variable, making it easier to code.
question1 = eval(str(q1p1) + operation + str(q1p2))


#This asks for the user’s name

name = input("What is your forename (With No Caps?)")
surname = input("What is your surname (With No Caps?)")


#This prints a welcome message, personalised with the user's name

print("Welcome to your test," + name)


#Information about how to answer questions

print('''Throughout your test you will be asked a series of questions.
These questions will be randomly generated and are designed to test your basic arithmetic skills.
Please enter your answers in integer form.
EG. if the question was 5 + 5, you would enter 10 with no spaces or extra characters.''')



#First question

print (question1)
answer1 = input("What is the answer to the above question?")
if (question1) == True:
    print("Well done, you got it correct!")
    (score) + 1

Answer 1

我运行了代码并收到以下错误：

无法将'list'对象隐式转换为str

为该行：

question1 = eval(str(q1p1) + operation + str(q1p2))

操作是一个列表，您正在尝试打印字符串中的操作列表。这不会像你期望的那样工作，你需要选择一个单独的操作，例如：

question1 = eval(str(q1p1) + str(operation[2]) + str(q1p2))

我认为你的程序不像你期望的那样工作。您正在尝试创建一个问题字符串，然后检查这个“问题1”是否属实？以下是您的计划应该做的一些步骤：

从操作列表中选择一项操作，不能使用整个列表。
生成两个随机数（查找Python'随机'类）
检查您从列表中选择的操作，使用此操作执行两个数字的计算
从用户那里获取输入（查找Python'输入'方法）

检查用户输入是否与正确答案匹配

import random

operations = ['+','-','x']

operation = random.choice(operations)

number1 = random.randrange(0,10)
number2 = random.randrange(0,10)

score = 0

answer = None

if operation == '+':
    answer = number1 + number2
elif operation == '-':
    answer = number1 - number2
elif operation == 'x':
    answer = number1 * number2

user_answer = input("What is " + str(number1) + " " + operation + " " + str(number2) + "?")
user_answer = float(user_answer)

if user_answer == answer:
    print("Correct")
    score = score+1

也是行

score + 1

不执行您认为的操作，它只需要得分并为其添加一个，它不会对此值执行任何操作。要提高分数，您需要将其重新分配回分数：

score = score + 1

Answer 2

“x”不是python中的乘法运算符，请使用'*'

调试时，最好使用print在代码中显示有趣变量的值。

例如，当您在代码中的某一行看到错误并且您不确定原因时。尝试打印该行使用的值。

例如，将代码更改为以下内容：

print( 'eval called with', str(q1p1) + operation + str(q1p2) )
question1 = eval(str(q1p1) + operation + str(q1p2))

python中的eval模块出错

2 个答案: