在Python中，如果输入有效，如何使条件if循环不执行

Question

#Write a short program that will do the following
#Set a value your favorite number between 0 and 100
#Ask the user to guess your favorite number between 0 and 100
#Repeat until they guess that number and tell them how many tries it took
#If the value they guessed is not between 0 and 100
#tell the user invalid guess and do not count that as an attempt

我的问题是，即使用户猜测0到100之间的数字，它仍然打印出"无效猜测"。再试一次"。我如何控制我的循环跳过打印语句和问题重复，如果它是可接受的输入(1-100)?提前感谢!

favoriteNumber = 7
attempts = 0
guess = raw_input("Guess a number between 0 and 100: ")
if (guess  < 0) or (guess > 100):
    print "Invalid guess. Try again"
    guess = raw_input("Guess a number between 0 and 100: ")
attempts1 = str(attempts)
print "it took " + attempts1 + "attempts."

Answer 1

使用input而不是raw_input，所以你得到的是整数而不是字符串

favoriteNumber = 7
attempts = 0

while True:
    guess = input("Guess a number between 0 and 100: ")
    if (guess  < 0) or (guess > 100):
        attempts=attempts+1
        print "Invalid guess. Try again"
    else:
        attempts=attempts+1
        break
attempts1 = str(attempts)
print "it took " + attempts1 + " attempts."

Answer 2

在Python 2.7.10中，如果你不将字符串转换为整数，它会接受它，但所有适用于数字的规则都会返回false。下面是一个工作示例:

favoriteNumber = 7
attempts = 0
guess = raw_input("Guess a number between 0 and 100: ")
if (int(guess)  < 0) or (int(guess) > 100):
    print "Invalid guess. Try again"
    guess = raw_input("Guess a number between 0 and 100: ")
attempts1 = str(attempts)
print "it took " + attempts1 + " attempts."

在Python 3.4中，原始代码会产生一个错误，告诉您它是字符串而不是整数。但是，正如Paul所说，您可以将raw_input放在int()命令中。

Answer 3

你raw_input返回一个字符串，它总是> 100。使用int(raw_input())