[SOLVED] 代写 4. TYPE → integer | real |

4. TYPE → integer | real |
string
error: Data type expected
5. CMPD_STMT → begin
6. OPT_STMTS → 
OPT_STMTS end |
STMT_LIST
7. STMT_LIST → STMT STMT_LIST_END
8. STMT_LIST_END → 9.STMT→ id:=EXPR
; STMT_LIST | 
CMPD_STMT
if COND then STMT else STMT while COND do STMT
error: Beginning of statement expected
10. COND → EXPR RELOP EXPR 11. EXPR → VAL EXPR_END
| | |
Mini PASCAL Grammar
Key
ALL_CAPS
Non-Terminals
lower case and symbols
Terminals (Tokens)
|
grammar metasymbol OR Ab|c == Ab Ac
{ term, term, .. }
Select1 Set
0. PROGRAM → program id ; DECLARATIONS CMPD_STMT . period 
1. ID_LIST → id ID_LIST_END
2. ID_LIST_END → , ID_LIST |

3. DECLARATIONS → var ID_LIST : TYPE ; DECLARATIONS |       
{,}
{ default }
{ var } {default}
{ integer } { real }
{ string }
{ end }
{ default }
{;}
{ default }
{ id }
{ begin } { if }
{ while }

12. EXPR_END → ARITH_OP VAL EXPR_END | 
you can figure out select sets for the rest
13.ARITH_OP→+ | – | * | / error: arithmetic operator expected
14. RELOP→< | <= | > | >= | <> | = error: relational operator expected
15. VAL→ id| int_lit | real_lit | char_lit | ( EXPR ) |
SIGN VAL
error: value expected
16. SIGN→+|− error: sign expected
{ + – * / } { default }