Yacc – My Humble Abode

yacc program to implement arithmetic operators

September 16, 2013 by Humble

Lex program %{ #include<stdio.h> #include<stdlib.h> %} %% [0-9]+ {yylval=atoi(yytext);return (NUM);} “+”|”-“|”*”|”/”|”\n” {return yytext[0];} %% Yacc program %{ #include<stdio.h> #include<ctype.h> int i=0; %} %token NUM %left ‘+”-‘ %left ‘*”/’ %% S:E ‘\n’ {printf(“result =%d”,(int)$$);} ; E:E’+’E {$$=$1+$3;} |E’-‘E {$$=$1-$3;} |E’*’E {$$=$1*$3;} |E’/’E {$$=$1/$3;} |NUM {$$=$1;} ; %% #include “lex.yy.c” main() { yyparse(); } int …

yacc program to implement logical operators

May 16, 2020September 16, 2013 by Humble

Lex program %{ #include<stdio.h> #include<stdlib.h> %} %% (0|1)+ {yylval=atoi(yytext);return (NUM);} “&”|”|”|”!”|”x”|”\n” {return yytext[0];} %% yacc program %{ #include<stdio.h> #include<ctype.h> int i=0; %} %token NUM %left ‘&”|”x’ %right ‘!’ %% S:E ‘\n’ {printf(“result =%d”,(int)$$);} ; E:E’&’E {$$=$1&$3;} |E’|’E {$$=$1|$3;} |’!’E {$$=!$2;} |E’x’E {$$=($1&(!$3))|((!$1)&$3);} |NUM {$$=$1;} ; %% #include “lex.yy.c” main() { yyparse(); } int yywrap() {} …