- 97 名前：デフォルトの名無しさん mailto:sage [2019/08/11(日) 06:08:19.60 ID:0wbGlMwh.net]
- >>91 Ruby
f = -> a {a.sort.group_by{|e| a.count(e)}[1]&.min || -1}
[
[1,1,1,1,2,2,2,3,3,4],
[1,2,3,4,5,5,4,3,2,1],
[3,1,4,1,5,9,2,6,5,3,5]
].each{|a| puts '%p => %s' % [a, f[a]]} # =>
[1, 1, 1, 1, 2, 2, 2, 3, 3, 4] => 4
[1, 2, 3, 4, 5, 5, 4, 3, 2, 1] => -1
[3, 1, 4, 1, 5, 9, 2, 6, 5, 3, 5] => 2
