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a[-b]c
a[^]b]c
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a[b-]c
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a(b*|c)d
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a[ab][ab][ab][ab][ab][ab][ab][ab][ab][ab][ab][ab][ab][ab][ab][ab][ab][ab][ab][ab]
a[ab][ab][ab][ab][ab][ab][ab][ab][ab][ab][ab][ab][ab][ab][ab][ab][ab][ab][ab][ab](wee|week)(knights|night)
12345678901234567890123456789
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(wee|week)(knights|night)
(we|wee|week|frob)(knights|night|day)
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a(bbb+|bb+|b)b
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a(b|c){0,0}d
a(b|c){0,1}d
a(b|c){0,1}d
a(b|c){0,2}d
a(b|c){0,2}d
a(b|c){0,}d
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a(b|c){1,1}d
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a(b|c){1,2}d
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