Python 返回第一个输入的偶数/奇数答案

【问题标题】：Python return the first entered even/odd numberPython 返回第一个输入的偶数/奇数
【发布时间】：2021-07-07 05:44:11
【问题描述】：

下面的代码要求用户连续输入一个整数，直到他们输入 EXIT。一旦他们输入 EXIT，系统将返回第一个输入的奇数和偶数。到目前为止，我只设法让它打印总数。我尝试过使用两个 while 循环，一个处理偶数，另一个处理奇数，但我仍然得到相同的结果

我已经在下面包含了我的输出和预期的输出。

注意。我们还没有学习列表或类似的东西，所以它们不能被使用

代码

even_count = 0
odd_count = 0

while True:
 user_input = input("Enter an integer (or EXIT to quit): ")

 if (user_input == "EXIT"):
  break

 number = int(user_input)

 if (number%2 == 0):
  even_count += 1
  print("The first even number you entered is {0}".format(even_count))
 else:
  odd_count += 1
  print("The first odd number you entered is {0}".format(odd_count))

CURRENT OUTPUT（打印总计数）

Enter an integer (or EXIT to quit): 1
Enter an integer (or EXIT to quit): 3
Enter an integer (or EXIT to quit): 5
Enter an integer (or EXIT to quit): 2
Enter an integer (or EXIT to quit): 4
Enter an integer (or EXIT to quit): 6

Enter an integer (or EXIT to quit): EXIT
The first even number you entered is 3
The first odd number you entered is 3

预期输出（打印第一个输入的数字）

Enter an integer (or EXIT to quit): 1
Enter an integer (or EXIT to quit): 3
Enter an integer (or EXIT to quit): 5
Enter an integer (or EXIT to quit): 2
Enter an integer (or EXIT to quit): 4
Enter an integer (or EXIT to quit): 6

Enter an integer (or EXIT to quit): EXIT
The first even number you entered is 2
The first odd number you entered is 1

【问题讨论】：

创建两个变量even和odd用-1初始化它们只有在值为-1时才改变它们

标签： python

【解决方案1】：

你可以创建一个包含第一个偶数的变量：

代码：

first_even_num = None
first_odd_num = None

while True:
    user_input = input("Enter an integer (or EXIT to quit): ")

    if (user_input == "EXIT"):
        break

    number = int(user_input)

    if (number%2 == 0):
        if first_even_num is None:
            first_even_num = number
    else:
        if first_odd_num is None:
            first_odd_num = number


print("The first even number you entered is {0}".format(first_even_num))
print("The first odd number you entered is {0}".format(first_odd_num))

【讨论】：