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added 101 characters in body

edited Dec 31, 2018 at 21:37

Perl 6, 6262 57 bytes

~~{(0,{$-@+@2($!>@||$-@∈@)given @[-1]}...)[^$]}~~

{(0,{$_-@_+@_*2*($_$!>@_||$_=@_[*-@_∈@_1])given @_[*+@_-1]@_*2*($!>@_&&$!-@_∉@_)}...*)[^$_]}

Try it online!-5 bytes thanks to Jo King

{(0,{$_-@_+@_*2*($_!>@_||$_-@_∈@_)given @_[*-1]}...*)[^$_]}

~~{(0,{$-@+@2($!>@||$-@∈@)given @[-1]}...)[^$]}~~

{(0,{($!=@_[*-1])+@_-@_*2*($!>@_&&$!-@_∉@_)}...*)[^$_]}

-5 bytes thanks to Jo King

answered Dec 31, 2018 at 6:18

{(0,{$_-@_+@_*2*($_!>@_||$_-@_∈@_)given @_[*-1]}...*)[^$_]}