Question

我正在尝试用Python编写一个程序，告诉我一件事，如果输入的数字介于1和100之间。这是我到目前为止的代码：

number = int (raw_input ("give me a number."))

if number < 100 and number > 1:
    print ("Great! The number " + number + " is in fact between 1 and 100. I am happy " + number + " times")

if number < 1 or number < 100:
    print ("Not so great! The number " + number + " is not between 1 and 100.")

我可以运行第一位，但是一旦输入介于1和100之间的数字，我就会收到此错误：

Traceback (most recent call last):
  File "/Downloads/number (1).py", line 3, in <module>
    print "Great! " + number + " is in fact between 1 and 100"
TypeError: cannot concatenate 'str' and 'int' objects

我该如何解决这个问题？

Answer 1

您无法直接合并int和str。转换为字符串或使用字符串格式：

优选：

print ("Not so great! The number {} is not between 1 and 100.".format(number))

有一点已经弃用了，现在仍然坚持，但被认为是“老”：

print ("Not so great! The number %i is not between 1 and 100." % number)

最明确，最慢，最不喜欢和最糟糕的风格（感谢@Stefano Sanfilippo！）：

print ("Not so great! The number " + str(number) + " is not between 1 and 100.")

如果你有"5" + 5，你想要什么？您想要10，还是想要"55"？由于含糊不清，提出错误并强迫您明确表达意图是更安全的

Answer 2

您需要将'number'转换为字符串。您可以使用'str'函数将其包装起来。

Answer 3

这应该有效：

print ("Great! The number "+str(number)+" is in fact between 1 and 100. I am happy " +str(number)+" times")

Answer 4

您不能直接将字符串和整数一起添加。这样做会抛出TypeError：

>>> 'a' + 1
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
TypeError: Can't convert 'int' object to str implicitly
>>>

相反，您可以使用str.format将整数插入字符串中：

print("Not so great! The number {0} is not between 1 and 100.".format(number))

此外，比较的逻辑是错误的。例如，这个if语句的条件：

if number > 1 or number < 100:

将始终评估为True，因为number 总是大于1或小于100。

解决了这些问题后，您的代码应如下所示：

number = int(raw_input("give me a number.")) # You can chain comparisons if 1 < number < 100: print("Great! The number {0} is in fact between 1 and 100. I am happy {0} times".format(number)) # You should use else here else: print("Not so great! The number {0} is not between 1 and 100.".format(number))

输入数字时出现Python错误

4 个答案: