意外的回路输出

Question

该代码输出00000000，但我认为它将输出00000011，因为最后两个索引满足if条件。

import pygame
numbers = [pygame.Color("#FFFFFF"),
            pygame.Color("#FFFFFF"),
            pygame.Color("#FFFFFF"),
            pygame.Color("#FFFFFF"),
            pygame.Color("#FFFFFF"),
            pygame.Color("#FFFFFF"),
            pygame.Color("#FF0000"),
            pygame.Color("#FF0000")]

x = 0
binary = ""
for number in numbers:
    print(number)
    if numbers[x] == pygame.Color("#FF0000"):
        binary += "1"
    elif numbers[x] == pygame.Color("#FFFFFF"):
        binary += "0"
print("after: ", binary)  

Answer 1

将您的循环更改为此：

for number in numbers:
    print(number)
    if number == pygame.Color("#FF0000"):
        binary += "1"
    elif number == pygame.Color("#FFFFFF"):
        binary += "0"

numbers[x]将始终指向第一个元素，因为您没有递增x 。 因此，将numbers[x]更改为number 。

Answer 2

如果您想使用索引，可以更改代码，如下所示：

binary = ""
for x, number in enumerate(numbers):
    print(number) # number = numbers[x]
    if numbers[x] == pygame.Color("#FF0000"):
        binary += "1"
    elif numbers[x] == pygame.Color("#FFFFFF"):
        binary += "0"
print("after: ", binary)