EBNF für vom Parser erkannte Grammatik:

G(T,N,s,R)

T:	NUM 'z', '+', '-', '*', '/', '^', 's', 'c', 'e', '§'
N:	expr, term, fac, pot, prim
s:	expr
R:
(1) <expr>	->	<term> { '+' <term> } | <term> { '-' <term> } .
(2) <expr>	->	<fact> { '*' <fact> } | <fact> { '/' <fact> } .
(3) <fact> 	->	's' <pot> | 'c' <pot> | 'e' <pot> | '§' <pot> | <pot>.
(4) <pot> 	->	<prim> '^' <prim> | <prim> .
(5) <prim>	->	'z' | NUM | '(' <expr> ')' .