野牛问题 reduce/reduce 冲突

Question

所以我是 Bison 的新手，我正在尝试制作一个简单的计算器。当我执行 bison -d 命令时，它说有 7 reduce/reduce 冲突，我不太确定为什么会这样，我知道这是因为我的语法中有一些错误的逻辑，我就是找不到它。所以这是 .y 文件的代码：

%{
#include <stdio.h>
#include <stdlib.h>
#include <Math.h>

char** nizVarijabliI;
int* nizVrijednostiVarijabliI;
int* nizIinfo;
char** nizVarijabliD;
float** nizVrijednostiVarijabliD;
int* nizDinfo;
int countD = 100;
int dountI = 100;
void updateSymbolTableI(char* s,int br);
void updateSymbolTableD(char* s,float br
float symbolVal(char* s)

%}
%union{
    double var1;
    int var2;
    char* varName;
}
%token <var1> DNUM
%token <var2> INUM
%token <varName> VARIABLE;
%token QUIT PLUS MINUS DIVIDE MULTIPLY EQUALS EXPONENTIATION SIN COS LOG POW SQRT LPAREN RPAREN NEWLINE
%right EQUALS
%left PLUS MINUS
%left DIVIDE MULTIPLY
%right EXPONENTIATION
%nonassoc UMINUS
%type <var1> mixExp
%type <var2> exp
%type <varName> assign
%start pocetak
%%
pocetak :
            |   pocetak line;

line :  NEWLINE
        |   assign  NEWLINE {;}
        |   mixExp  NEWLINE {printf("%f\n",);}
        |   exp     NEWLINE {printf("%d\n",);}
        |   QUIT        NEWLINE {exit(1);}
        ;

mixExp  :   DNUM                                                NEWLINE {$$ = ;}
            |   SIN LPAREN mixExp RPAREN                    NEWLINE {$$ = sin();}
            |   COS LPAREN mixExp RPAREN                    NEWLINE {$$ = cos();}
            |   LOG LPAREN mixExp RPAREN                    NEWLINE {$$ = log();}
            |   SQRT LPAREN mixExp RPAREN                   NEWLINE {$$ = sqrt();}
            |   POW LPAREN mixExp "," mixExp RPAREN NEWLINE {$$ = pow(,);}
            |   VARIABLE                                            NEWLINE {$$ = symbolVal();}
            |   MINUS mixExp    %prec   UMINUS              NEWLINE {$$ = -:}
            |   mixExp PLUS mixExp                              NEWLINE {$$ =  + ;}
            |   mixExp MINUS mixExp                         NEWLINE {$$ =  - ;}
            |   mixExp MULTIPLY mixExp                      NEWLINE {$$ =  * ;}
            |   mixExp DIVIDE mixExp                            NEWLINE {$$ =  / ;}
            |   LPAREN mixExp RPAREN                            NEWLINE {$$ = ;}
            |   mixExp PLUS exp                                 NEWLINE {$$ =  + ;}
            |   mixExp MINUS exp                                NEWLINE {$$ =  - ;}
            |   mixExp MULTIPLY exp                         NEWLINE {$$ =  * ;}
            |   mixExp DIVIDE exp                               NEWLINE {$$ =  / ;}
            |   exp PLUS mixExp                                 NEWLINE {$$ =  + ;}
            |   exp MINUS mixExp                                NEWLINE {$$ =  - ;}
            |   exp MULTIPLY mixExp                         NEWLINE {$$ =  * ;}
            |   exp DIVIDE mixExp                               NEWLINE {$$ =  / ;}
            ;
exp     :   INUM                                                    NEWLINE {$$=;}
            |   SIN LPAREN exp RPAREN                       NEWLINE {$$=sin();}
            |   COS LPAREN exp RPAREN                       NEWLINE {$$=cos();}
            |   LOG LPAREN exp RPAREN                       NEWLINE {$$=log();}
            |   SQRT LPAREN exp RPAREN                      NEWLINE {$$=sqrt();}
            |   POW LPAREN exp "," exp RPAREN               NEWLINE {$$ = pow(,);}
            |   VARIABLE                                            NEWLINE {$$ = symbolVal();}
            |   MINUS exp   %prec   UMINUS                  NEWLINE {$$ = -:}
            |   exp PLUS exp                                        NEWLINE {$$ =  + ;}
            |   exp MINUS exp                                   NEWLINE {$$ =  - ;}
            |   exp MULTIPLY exp                                NEWLINE {$$ =  * ;}
            |   exp DIVIDE exp                                  NEWLINE {$$ =  / ;}
            |   LPAREN exp RPAREN                               NEWLINE {$$ = ;}
            ;
assign  :   VARIABLE EQUALS exp                         NEWLINE {updateSymbolTableI(,);}
            |   VARIABLE EQUALS mixExp                      NEWLINE {updateSymbolTableD(,);}
            ;
%%
int main() {
    int i;
    nizVrijednostiVarijabliI = malloc(100*sizeof(int));
    nizVrijednostiVarijabliD = malloc(100*sizeof(float));
    nizIinfo = malloc(100*sizeof(int));
    nizDinfo = malloc(100*sizeof(int));
    for(i=0;i<100;i++) {nizIinfo[i] = 0; nizDinfo[i] = 0;}
    nizVarijabliI = malloc(100*sizeof(char*));
    for(i=0;i<100;i++) nizVarijabliI[i] = malloc(100*sizeof(char));
    nizVarijabliD = malloc(100*sizeof(char*));
    for(i=0;i<100;i++) nizVarijabliD[i] = malloc(100*sizeof(char));
    yyparse();
    return;
}
void updateSymbolTableI(char* s,int br)
{
    int freeInd = -1;
    int i;
    for(i=0;i<countI;i++)
    {
        if(nizIinfo[i] == 0)
        {
            freeInd = i;
            break;
        }
    }
    if(freeInd == -1)
    {
        freeInd = i;
        countI = countI * 2;
        nizVrijednostiVarijabliI = realloc(nizVrijednostiVarijabliI,count*sizeof(int));
        nizIinfo = realloc(nizIinfo,count*sizeof(int));
        nizVarijabliI = realloc(nizVarijabliI,count*sizeof(char*));
    }
    nizVrijednostiVarijabliI[freeInd] = br;
    nizIinfo[freeInd] = 1;
    nizVarijabliI[freeInd] = s;
}
void updateSymbolTableD(char* s, float br)
{
    int freeInd = -1;
    int i;
    for(i=0;i<countD;i++)
    {
        if(nizDinfo[i] == 0)
        {
            freeInd = i;
            break;
        }
    }
    if(freeInd == -1)
    {
        freeInd = i;
        countD = countD * 2;
        nizVrijednostiVarijabliD = realloc(nizVrijednostiVarijabliD,count*sizeof(float));
        nizDinfo = realloc(nizDinfo,count*sizeof(int));
        nizVarijabliD = realloc(nizVarijabliD,count*sizeof(char*));
    }
    nizVrijednostiVarijabliD[freeInd] = br;
    nizDinfo[freeInd] = 1;
    nizVarijabliD[freeInd] = s;
}
float symbolVal(char* s)
{
    int ind = -1;
    int i;
    for(i=0;i<countI;i++)
    {
        if(strcmp(s,nizVarijabliI[i]) == 0)
        {
            ind = i;
            return (float)nizVrijednostiVarijabliI[ind];
        }
    }
    if(ind == -1)
    {
        for(i=0;i<countD;i++)
        {
            if(strcmp(s,nizVarijabliD[i]) == 0)
            {
                ind = i;
                return nizVrijednostiVarijabliD[ind];
            }
        }
    }
    if(ind == -1) return 0;
}

还有我为此制作的 lex 文件：

%{
#include "ultcalc.tab.h";
%}
%%
"quit"                              {return QUIT;}
"sin"                               {return SIN;}
"cos"                               {return COS;}
"pow"                               {return EXPONENTIATION;}
"log"                               {return LOG;}
"sqrt"                              {return SQRT;}
[0-9]+"."[0-9]+             {yylval.var1 = atof(yytext); return DNUM;}
[a-z][a-zA-Z0-9]*           {yylval.varName = yytext; return VARIABLE;}
[0-9]+                          {yylval.var2 = atoi(yytext); return INUM;}
"="                             {return EQUALS;}
"+"                             {return PLUS;}
"-"                                 {return MINUS;}
"*"                             {return MULTIPLY;}
"/"                                 {return DIVIDE;}
"("                                 {return LPAREN;}
")"                                 {return RPAREN;}
","                                 {return yytext;}
[ \t]                               {;}
[\n]                                {return NEWLINE;}
.                                   {yyerror("Neocekivani karakteri!");}
%%
yywrap() {return 1;}

如有任何建议，我们将不胜感激。

Answer 1

我通过简化语法以仅接受所有数字而不在解析时区分整数和浮点数来修复 reduce/reduce 冲突的主要问题，而我稍后将所有数字转换为浮点数在 C 代码中. @rici在评论中提到了一些更底层的问题，我也修复了它们并在上面的评论区中解释了（所以我不再重复）。

野牛问题 reduce/reduce 冲突

Bison issue with reduce/reduce conflict

yacc

bison

reduce-reduce-conflict