Why 'a' is not a legitimate constants and ABC is legal constants?-CodePudding

CodePudding user response:

ABC is not legitimate constants, but can be a constant names,

CodePudding user response:

reference 1st floor ctrigger response:

ABC is not legitimate constants, but can be a constant names,

B legal? I feel quite legitimate

CodePudding user response:

I also think B is legal, isn't an escape character? The answer right?

CodePudding user response:

Option A, not constants
Line selection B is constant, the escape character, the view of the definition of ASCII escape character,
In C, constitutes a control character constants must be enclosed in escape character said,
Escape character is a kind of begin with '\' characters, such as back space with '\ b, said a newline with' \ n ', said
In the escape character '\' said behind it has lost its original meaning of characters, into another special meanings,

Option C is not a constant, is a string, because live in double quotation marks, not constants
Option D are constants, octal,

No idea what the answer is

CodePudding user response:

refer to the second floor Reshitian123 response:

Quote: refer to 1st floor ctrigger response:
ABC is definitely not the legitimate constants, but can be a constant names,

B legal? I feel quite legitimate

Choose A, is not A constant,
B: character constants
C: string constants
D: octal constants