digit ::= “0-9″;

name ::= letter { letter | digit };

integer ::= digit { digit };

ident ::= name | function_call;

function_call ::= name “(” [expr {, expr}] “)”;

factor ::= (ident | integer | “(” expr “)” );

unary_factor ::= [“+”|”-“] factor;

term1 ::= [“*”|”/”] factor;

term0 ::= factor { term1 };

first_term ::= unary_factor term1;

math_expr ::= first_term { [“+”|”-“] term0 }

rel_expr ::= math_expr (“==”|”!=”|”<“|”>”|”>=”|”<=”) math_expr;

not_factor ::= [“!”] rel_expr;

term_bool ::= not_factor { (“&” | “&&”) not_factor };

bool_expr ::= term_bool { (“|” | “^”) term_bool };

expr ::= bool_expr;

assign = ident “=” expr;

assign_stmt ::= assign “;” ;

if_stmt ::= “if” “(” expr “)” stmt_block [ “else” inner_block ];

while_stmt ::= “while” “(” expr “)” inner_block;

for_stmt ::= “for” “(” assign “;” expr “;” assign “)” inner_block

break_stmt ::= “break” “;”;

cont_stmt ::= “continue” “;”;

ret_stmt ::= “return” expr “;”;

stmt ::= (

if_stmt

| while_stmt

| for_stmt

| break_stmt

| cont_stmt

| ret_stmt

| assign_stmt

);

inner_block ::= “{” { stmt } “}”;

outer_block ::= “{” { inner_decl } { stmt } “}”;

inner_decl ::= [ class ] type ident { “,” ident } “;”;

class ::= “extern” | “static” | “auto”;

type ::= “int” | “void”;

params ::= type ident { , type ident };

outer_decl ::= [ class ] type ident { “,” ident } “;”;

func_decl ::= [ class ] type ident “(” params “)” outer_block;