Post History
Solutions by ngn https://chat.stackexchange.com/transcript/message/57690032#57690032 APL 17: {⍵[⍋⍋⍉⊖2⊥⍣¯1⍳≢⍵]} ngn/k 13: {x@<<+|2\!#x} These are too good not to post.
Answer
Solutions by ngn https://chat.stackexchange.com/transcript/message/57690032#57690032 APL 17: {⍵[⍋⍋⍉⊖2⊥⍣¯1⍳≢⍵]} ngn/k 13: {x@<<+|2\!#x} These are too good not to post.