Parsing 转换/减少cup解析器中的冲突

我写了以下语法：

/* Precedences */ 
precedence left UMINUS;
precedence left ID;

Expr ::=      ID:e              
    | NUM:e             

    | Expr:e1 TIMES Expr:e2     

    | LP Expr:e RP          

    ;

Call ::= ID:id LP  ExprComma:args RP  ; 

当我尝试在此程序上运行解析器时：

weirdAverage(5)

（标记为：id lp num（即expr）rp）

我得到：

 Syntax error in line 1 '('

因此，我尝试删除以下内容：

 precedence left ID;

现在我得到一个错误：

   [java] Warning : *** Shift/Reduce conflict found in state #16
 [java]   between Expr ::= ID (*) 
 [java]   and     Call ::= ID (*) LP ExprComma RP 
 [java]   under symbol LP
 [java]   Resolved in favor of shifting.
 [java] Warning : *** Shift/Reduce conflict found in state #79
 [java]   between Expr ::= ID (*) 
 [java]   and     Call ::= ID (*) LP ExprComma RP 
 [java]   under symbol LP
 [java]   Resolved in favor of shifting.
 [java] Error : *** More conflicts encountered than expected -- parser generation aborted