TM as a Language Acceptor
Definition: Let M = (Q, S, G, R, s, F) be a TM. The language accepted by M, L(M), is defined as:   
L(M) = {w: w Î S*, sw |–* xfy; x, y Î G*, f Î F} È
              {e: sD |–* xfy; x, y Î G*, f Î F}
M accepts w by a sequence of moves from s to a final state.
 Gist:
Illustration:
w
s
x
y
f
• For w ¹ e:
D
D
…
D
D
…
s
x
y
f
• For w = e:
D
D
…
D
D
…
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