Lex is a computer program that generates lexical analyzers.
Lex reads an input stream specifying the lexical analyzer and outputs source code implementing the lexer in the C programming language.
The commands for executing the lex program are:
lex abc.l (abc is the file name) cc lex.yy.c -efl ./a.out
Let’s see to accept a valid integer and float value
using lex program.
Input : -77.99 Output : Valid Float Value Input : fghj Output : Not a valid Integer/ Float number
Below is the implementation:
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