PDA Configuration
Definition: Let M = (Q, S, G, R, s, S, F) be a PDA.
A configuration of M is a string c Î G*QS*
 Gist: Instantaneous description of PDA
Configuration
Am
A1
A2
…
ai
an
…
a1
a2
…
Read-write head
Read head
Finite State Control
Pushdown:
Input tape:
p
= current state
p
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