COMPILER DESIGN

Detailed explanation-1: -The Lookahead operator is the addition operator read by lex to distinguish different patterns for a token. A lexical analyzer is used to read one character ahead of a valid lexeme and then retracts to produce a token.

Detailed explanation-2: -By buffering input data, the compiler can access and process larger chunks of input data at once, rather than reading and processing input data one character at a time. There are several input buffering strategies used in compiler design, including block buffering, line buffering, and lookahead buffering.