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From: Hans-Peter Diettrich <DrDiettrich1@netscape.net>
Newsgroups: comp.compilers
Subject: Re: FIRST_k, FOLLOW_k, k>1
Date: Sat, 8 Feb 2020 11:00:48 +0100
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Am 06.02.2020 um 23:16 schrieb Andy:
> I search examples,
> E->aWbXYcdZ
> W->w
> X->x
> Y->y
> Z->z
>
> if for FIRST(k=4) wil be: E={awbx} W={wbxy} X={xycd} Y={ycdz} Z={z}
> what is convention?

Your grammar definitely is LL(1). You should provide a grammar that
requires longer lookahead.

IMO the FIRST set covers all *different* sequences, in your case
FIRST(E)={a} hence LL(1).
Only if there exist multiple alternatives starting with 'a' they have to
be listed as e.g. FIRST(E)={ax, ay}.

Dunno about the FOLLOW set, perhaps it can stay LL(1)?

DoDi