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Grammar
:
1 production per line
start nonterminal: left-hand side of first production
Remove: Right click on state ➞ 'Remove'
Productions
:
form: S -> X Y | a S b | \eps
left-hand side: a single nonterminal
right-hand side: groups of nonterminals and terminals separated by "|"
Nonterminals
:
form: one single upper case character A-Z
Terminals
:
allowed: abcdefghijklmnopqrstuvwxyz()[]{}
Empty word:
:
empty word: ε (write \epsilon or \eps or \e)
Problem
Find a grammar that recognizes the following
language
:
{a^n x b^n | n >=1 }
Grammar:
Common Mistakes