Find a solution similar to Polish expressions?

liberate10

My program needs to recognize character expressions such as: a> 11&&a <100&&b == 15 || c> 21&&d == 20, and the program finally returns a true or false value, such as the function bool bret = fun (String s); s is a> 1&&a <100&&b == 5 || c> 1&&d == 2 and other strings, there may be +-* / (), etc., this How to deal with it?

Thank you

1231456

Compilation principle
lex&&yacc

liberate10

Is there something like a> 11&&a <100&&b == 15 || c> 21&&d == 20 this kind of algorithm?

wxibing

Positive solution on the first floor