代码语句的token计数数量及方法正确性问询

Great question! Let's break this down step by step based on standard C language lexical rules (since your code resembles C syntax):

First, remember that comments are ignored during lexical analysis—so the //statement 1 and //statement 2 parts don't count as tokens at all. We only need to analyze the actual code before the comments.

Statement 1: int 1xab; #

Your count of 4 tokens is correct. Here's how the code splits into tokens:

• int: Keyword token
• 1: Integer literal token (decimal integer, since it starts with a digit and no 0x prefix)
• xab: Identifier token (starts with a letter, which is valid for C identifiers—even though placing it right after an integer literal creates a syntax error, the lexical analyzer still splits them as separate tokens)
• ;: Punctuator token (semicolon)

Statement 2: int 1 ; #

Your count of 3 tokens is also correct. The tokens here are:

• int: Keyword token
• 1: Integer literal token
• ;: Punctuator token

Key Note #

Even though int 1xab; is invalid C syntax (you can't have an integer literal directly followed by an identifier without an operator or other valid structure), the token splitting itself follows lexical rules correctly. The error would be caught during the syntax analysis phase, not the tokenization phase.

内容的提问来源于stack exchange，提问作者radhika