Comment by HolyBlackCat on Is writing else statement at the last mandatory in if-else ladder in C++?

Yes, it's legal. In general, An if-else-if ladder is not a special case, it's just a bunch of if else where the braces after else are omitted. It's easier to see if you indent the code like this: gcc.godbolt.org/z/hb8jddv9v