If statement if表达式的计算结果为False，但仍将执行它

输出为：

for i in range(6, 21):
for y in range(len(lst)):
    if i % lst[y] != 0 and i % 2 != 0 and i % 3 != 0 and i % 5 != 0 and i != lst[-1]:
        lst.append(i)
        print(lst)

---

那么，对于第二个七：7%3！=0（真）和i%2,3,5！=0（对）和我！=lst[-1]（7！=7->FALSE），为什么列表会附加第二个7？

您的代码，具有固定的缩进和初始值

lst

：

[2, 3, 5, 7, 7, 7, 11, 11, 11, 11, 11, 11, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 7]
[2, 3, 5, 7, 7, 7, 11, 11, 11, 11, 11, 11, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 7, 11]
[2, 3, 5, 7, 7, 7, 11, 11, 11, 11, 11, 11, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 7, 11, 13]
[2, 3, 5, 7, 7, 7, 11, 11, 11, 11, 11, 11, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 7, 11, 13, 17]
[2, 3, 5, 7, 7, 7, 11, 11, 11, 11, 11, 11, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19,    19, 19, 19, 19, 19, 19, 7, 11, 13, 17, 19]

告诉我：

lst=[2,3,5]
for i in range(6, 21):
    for y in range(len(lst)):
        if i % lst[y] != 0 and i % 2 != 0 and i % 3 != 0 and i % 5 != 0 and i != lst[-1]:
            lst.append(i)
            print(lst)

---

你确定你在你的问题中发布了相同的代码吗？

lst列表的初始内容是什么？对不起，lst的初始内容是->lst=[2,3,5]我得到了

[2,3,5,7,11,13,17,19]

最后。是的，打印方法的缩进程度是问题所在。谢谢是的，但是在shell中（我不知道为什么），我的输出在第一篇文章中。但是如果我打开一个新文件并复制粘贴代码，我会看到与您相同的输出。您可能忘记将

lst

重新调整为初始值，或者在缩进中出错。我无法复制您的输出，即使是在外壳中。谢谢您的回复。我还有一个问题：在条件I%lst[y]！=if表达式中的0，为什么将数字121添加到列表中，因为121%11！=0（FALSE）。当y等于0时，添加121。在这种情况下，您有：

121%2！=0和121%2！=0和121%3！=0和121%5！=0和121%119！=0

。

[2, 3, 5, 7]
[2, 3, 5, 7, 11]
[2, 3, 5, 7, 11, 13]
[2, 3, 5, 7, 11, 13, 17]
[2, 3, 5, 7, 11, 13, 17, 19]