Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

这里的else可以去掉 #1165

Open
HuanhuanYan547 opened this issue Apr 23, 2024 · 0 comments
Open

这里的else可以去掉 #1165

HuanhuanYan547 opened this issue Apr 23, 2024 · 0 comments

Comments

@HuanhuanYan547
Copy link

def is_prime(n):
if n<2:
return False
if n==2:
return True
for m in range(2,int(n**0.5)+1):
if (n%m)==0:
return False
else:
return True

for i in range(80,110):
if is_prime(i):
print(i)

变成下面这样:

def is_prime(n):
if n < 2:
return False
if n == 2:
return True
for m in range(2, int(n**0.5) + 1):
if n % m == 0:
return False
return True # 将这一行移出循环,并直接放在循环之后

for i in range(80, 110):
if is_prime(i):
print(i)

以下是GPT的解释
在这段代码中,else 语句的用法是正确的,但是它的位置可能会导致一些混淆。让我来解释一下:

当 for 循环结束时,如果没有在循环中遇到 return 语句(也就是没有返回值),那么就会执行 else 语句块。在这个特定的代码中,else 语句块紧跟在 for 循环后面,意味着只要 for 循环中没有 return 语句被执行,就会执行 else 语句块。
在这个例子中,else 语句块实际上不是必要的,因为它永远不会被执行。这是因为 for 循环中的 return 语句会在找到第一个除数时结束函数的执行,导致函数的返回值是 False。如果没有找到除数,for 循环会正常结束,然后返回 True,所以 else 语句块永远不会执行。

Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment
Labels
None yet
Projects
None yet
Development

No branches or pull requests

1 participant