Key of;
C = 0 (no #'s or b's)
G = 1 #
D = 2 #'s
A = 3 #'s
E = 4 #'s
B = 5 #'s
F#=6 #'s
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F = 1 b
Bb = 2 b's
Eb = 3 b's
Ab = 4 b's
Db = 5 b's
Gb = 6 b's
Notice that A = 3 #'s and each note beside A (Bb) and (Ab) take 1 more or 1 less b note to complete it's Key.