error c2181: illegal else without matching if

错误C2181：没有匹配的if，非法的else。

这个错误通常是由于代码中if和else语句的数量不匹配导致的。在编写代码时，应该仔细检查if和else语句的数量和位置，确保它们是正确的。如果出现这个错误，可以通过添加或删除if或else语句来解决它。

相关问题

error c2181: illegal else with

该错误为编译错误，提示有非法的else语句。可能原因是else语句前没有相应的if语句与其匹配，或者if语句后没有花括号包裹代码块导致else语句判断错误。需要检查代码中的if和else语句是否匹配，并检查代码中的括号和代码块是否正确。

illegal else without matching if

This is a syntax error that occurs when an else statement is used without a corresponding if statement. In programming, the else statement is used to specify what should happen when a certain condition is not met. However, for the else statement to be valid, there must be a previous if statement to which it corresponds.

For example, consider the following code:

if x > 0:
    print("x is positive")
else:
    print("x is not positive")

In this code, the else statement is used to specify what should happen if the condition in the if statement (x > 0) is not met. If x is greater than 0, the first statement will be executed. If not, the second statement will be executed.

If you were to remove the if statement and just leave the else statement, you would get an "illegal else without matching if" error:

else:
    print("x is not positive")

This is because there is no if statement to which the else statement corresponds. To fix this error, you need to add the if statement back in or remove the else statement entirely.