如果python中的语句不打印

Question

我正在为学校做作业，这个程序非常简单，但是我的 if 语句不能正常工作。有人知道为什么吗？代码如下：

letter = input("Name one of the most common letters in wheel of fortune puzzles: ")

if letter == "r":
    print(letter, "is one of the most common letters!")
if letter == "s":
    print(letter, "is one of the most common letters!")
if letter == "t":
    print(letter, "is one of the most common letters!")
if letter == "l":
    print(letter, "is one of the most common letters!")
if letter == "n":
    print(letter, "is one of the most common letters!")
if letter == "e":
    print(letter, "is one of the most common letters!")

else:
    print("Incorrect!")
    letter = input("Name one of the most common letters in wheel of fortune puzzles: ")


input("\n\nPress the enter key to exit:")

输出是：

Name one of the most common letters in wheel of fortune puzzles: j
Incorrect!
Name one of the most common letters in wheel of fortune puzzles: r


Press the enter key to exit:

Answer 1

我会这样写：

# Assumes Python 3
# Python 2: Use `raw_input` instead of input

common_letters = 'rstlne'
prompt = "Name one of the most common letters in wheel of fortune puzzles: "

while True:
    letter = input(prompt).strip()
    if letter in common_letters:
        print(letter, "is one of the most common letters!")
        break
    else:
        print("Incorrect!")
        answer = input('Type "end" to exit: ')
        if answer.strip() == 'end':
            break

我改变了一些东西：

1. 我使用了if letter in common_letters: 而不是那么多if 语句。这使您可以向/从common_letters 添加或删除另一个字母。

2. 我使用input(prompt).strip()去除多余的空白。

3. 如果没有输入常用字母，我会使用while True 循环一遍又一遍地重复问题。 break 终止此循环，即程序结束。

Answer 2

您需要输入"r" 或简单使用raw_input().raw_input 接受string 而input=eval(raw_input(prompt)).不是这种情况@所以它会搜索r 变量，除非你说@ 987654327@ 告诉它它是一个字符串。

Answer 3

您可以在您的代码中进行以下更改。

1. 从第二个if 条件将其更改为elif，因为如果您输入例如's'，那么它将进入第二个if 条件，并且else 部分也将运行。

2. 将input更改为raw_input示例更改

letter = input("Name one of the most common letters in wheel of fortune puzzles: ") 到

letter = raw_input("Name one of the most common letters in wheel of fortune puzzles: ")

Answer 4

#considering you enter 'j' and 'r' here's the path your code takes

letter = input("Name one of the most common letters in wheel of fortune puzzles: ")  
# letter now = 'j'

if letter == "r": # letter don't equal 'r', don't do next line
    print(letter, "is one of the most common letters!")
if letter == "s": # letter don't equal 's', don't do next line
    print(letter, "is one of the most common letters!")
if letter == "t": # letter don't equal 't', don't do next line
    print(letter, "is one of the most common letters!")
if letter == "l": # letter don't equal 'l', don't do next line
    print(letter, "is one of the most common letters!")
if letter == "n": # letter don't equal 'n', don't do next line
    print(letter, "is one of the most common letters!")
if letter == "e": # letter don't equal 'e', don't do next line
    print(letter, "is one of the most common letters!")

else: # because last if was false (letter don't equal 'e') do next line.
    print("Incorrect!") #  output : Incorrect!
# next line is not consider inside else. should be included within {} if desired
    letter = input("Name one of the most common letters in wheel of fortune puzzles: ") 
# letter now equals 'r'

#nothing to do with it


input("\n\nPress the enter key to exit:") 
# showing Press the enter key to exit: and waiting.

这会按照我的想法工作。

letter = raw_input("Name one of the most common letters in wheel of fortune puzzles: ")

if letter == "r":
    print(letter, "is one of the most common letters!")
elif letter == "s":
    print(letter, "is one of the most common letters!")
elif letter == "t":
    print(letter, "is one of the most common letters!")
elif letter == "l":
    print(letter, "is one of the most common letters!")
elif letter == "n":
    print(letter, "is one of the most common letters!")
elif letter == "e":
    print(letter, "is one of the most common letters!")
else:
    print("Incorrect!")

raw_input("\n\nPress the enter key to exit:")