LR Parsing for arithmetic expressions
I have got LR grammar and LR table for expressions like (1+1),1+(a+1)
0: E’->E
1: E ->E + T
2: E-> T
3: T ->T * F
4: T-> F
5: F ->( E )
6: F-> id
string[,] ActionTable =
//+ * ( ) id end E T F
{
{"" ,"" ,"S4" ,"" ,"S5" ,"" ,"1" ,"2" ,"3"}, // 0开发者_运维百科
{"S6" ,"" ,"" ,"" ,"" ,"AC" ,"" ,"" ,"" }, // 1
{"R2" ,"S7" ,"" ,"R2" ,"" ,"R2" ,"" ,"" ,""},//2
{"R4" ,"R4" ,"" ,"R4" ,"" ,"R4" ,"" ,"" ,""}, // 3
{"" ,"" ,"S4" ,"" ,"S5" ,"" ,"8" ,"2" ,"3"}, // 4
{"R6" ,"R6" ,"" ,"R6" ,"" ,"R6" ,"" ,"" ,""}, // 5
{"" ,"" ,"S4" ,"" ,"S5" ,"" ,"" ,"9" ,"3"}, // 6
{"" ,"" ,"S4" ,"" ,"S5" ,"" ,"" ,"" ,"10"},// 7
{"S6" ,"" ,"" ,"S11" ,"" ,"" ,"" ,"" ,""}, // 8
{"R1" ,"S7" ,"" ,"R1" ,"R1" ,"" ,"" ,"" ,""}, // 9
{"R3" ,"R3" ,"" ,"R3" ,"R3" ,"" ,"" ,"" ,""}, //10
{"R5" ,"R5" ,"" ,"R5" ,"R5" ,"" ,"" ,"" ,""} //11
};
I try to check expression like 1+1 or 1+(1*a)+1 but parser says that this expression is incorrect.
What can I do with my grammar to fix it?
You don't have a production rule for numbers.
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