flex-bison-in-action/analyzers/polynomials/polynomials.y

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%{
#include <stdio.h>
#include <stdlib.h>
void yyerror(const char *s);
int yylex(void);
%}
%union { int num; char var; }
%token <num> NUMBER
%token <var> VARIABLE
%token LPAREN RPAREN PLUS MINUS MULTIPLY
%%
input:
expr { printf("\033[92mParsing complete\033[0m\n"); }
;
expr:
term
| expr PLUS term { printf("Found operator: +\n"); }
| expr MINUS term { printf("Found operator: -\n"); }
;
term:
factor
| term MULTIPLY factor { printf("Found operator: *\n"); }
;
factor:
NUMBER { printf("Found number: %d\n", $1); }
| VARIABLE { printf("Found variable: %c\n", $1); }
| LPAREN expr RPAREN
;
%%
void yyerror(const char *s) {
fprintf(stderr, "Error: %s\n", s);
}
int main() {
printf("Enter a polynomial expression:\n");
yyparse();
return 0;
}