blob: 26a2007cd9aa6ca14685ba52c5f5b1f96a182a86 (
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%{
#include <stdio.h>
#include <stdlib.h>
int yylex();
int yyerror(char *);
%}
%token NUM ADD SUB MUL DIV LPAR RPAR
%left ADD SUB MUL DIV
%right NEG
%%
S:
E { printf("\n"); };
E:
E ADD E { printf("+ "); }
| E MUL E { printf("* "); }
| E SUB E { printf("- "); }
| E DIV E { printf("/ "); }
| LPAR E RPAR
| SUB E %prec NEG { printf("- "); }
| NUM { printf("%d ", yylval); }
;
%%
int main() {
yyparse();
}
int yyerror(char *s) {
printf("error: %s", s);
exit(0);
}
|
