Definition: Let M = (Q, S, R, s, F) be a WSFA, and let p, q Î Q, p ¹ q. States p and q are distinguishable if there exists w Î S* such that:
pw |–* p’ and qw |–* q’, where p’, q’ Î Q and  
((p’ Î F and q’ Ï F) or (p’ Ï F and q’ Î F));
otherwise, states p and q are indistinguishable
Distinguishable States
 Gist:
String w distinguishes states p and q if WSFA reaches a final state from precisely one of configurations pw and qw.
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