As it is known that Lexical Analysis is the first phase of compiler also known as scanner. It converts the input program into a sequence of Tokens.
A C program consists of various tokens and a token is either a keyword, an identifier, a constant, a string literal, or a symbol.
1) Keywords: Examples- for, while, if etc. 2) Identifier Examples- Variable name, function name etc. 3) Operators: Examples- '+', '++', '-' etc. 4) Separators: Examples- ', ' ';' etc
Below is a C program to print all the keywords, literals, valid identifiers, invalid identifiers, integer number, real number in a given C program:
'int' IS A KEYWORD 'a' IS A VALID IDENTIFIER '=' IS AN OPERATOR 'b' IS A VALID IDENTIFIER '+' IS AN OPERATOR '1c' IS NOT A VALID IDENTIFIER
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