可识别C语言语法的bison代码

以下是一个简单的bison代码示例，可识别C语言中的一些基本语法：

%{
#include <stdio.h>
%}

%token NUM ID IF ELSE WHILE RETURN
%token ADD SUB MUL DIV
%token LT LE GT GE EQ NE
%token ASSIGN SEMICOLON LPAREN RPAREN LBRACE RBRACE

%%

program: decl_list stmt_list
        ;

decl_list: /* empty */
         | decl_list declaration
         ;

declaration: type ID SEMICOLON
           ;

type: INT
    | FLOAT
    | CHAR
    ;

stmt_list: /* empty */
         | stmt_list statement
         ;

statement: expression SEMICOLON
         | compound_stmt
         | selection_stmt
         | iteration_stmt
         | return_stmt
         ;

compound_stmt: LBRACE stmt_list RBRACE
              ;

selection_stmt: IF LPAREN expression RPAREN statement
               | IF LPAREN expression RPAREN statement ELSE statement
               ;

iteration_stmt: WHILE LPAREN expression RPAREN statement
               ;

return_stmt: RETURN SEMICOLON
            | RETURN expression SEMICOLON
            ;

expression: assignment_expression
          ;

assignment_expression: ID ASSIGN expression
                      | equality_expression
                      ;

equality_expression: relational_expression
                    | equality_expression EQ relational_expression
                    | equality_expression NE relational_expression
                    ;

relational_expression: additive_expression
                      | relational_expression LT additive_expression
                      | relational_expression LE additive_expression
                      | relational_expression GT additive_expression
                      | relational_expression GE additive_expression
                      ;

additive_expression: multiplication_expression
                    | additive_expression ADD multiplication_expression
                    | additive_expression SUB multiplication_expression
                    ;

multiplication_expression: primary_expression
                          | multiplication_expression MUL primary_expression
                          | multiplication_expression DIV primary_expression
                          ;

primary_expression: ID
                   | NUM
                   | LPAREN expression RPAREN
                   ;

%%

int main(int argc, char *argv[]) {
    yyparse();
    return 0;
}

int yyerror(const char *s) {
    fprintf(stderr, "%s\n", s);
    return 0;
}

此示例包括C语言中常见的语法元素，如变量声明、赋值、控制流语句、表达式等。请注意，这只是一个简单的示例，实际上需要更复杂的语法规则才能完全识别C语言的语法。