我想根据最大键值返回一个哈希键/值对。我知道max_by
有效,但它会在第一个结果时停止。如果出现平局,我如何返回所有结果?
{
foo: 1,
bar: 3,
baz: 3
}.max_by { |key, value| value }
#=> [:bar 3] # Only bar comes back, but baz also has a value of 3.
我会做 :
hash = {
foo: 1,
bar: 3,
baz: 3
}
hash.group_by { |_,value| value }.max_by { |key,_| key }.last
# => [[:bar, 3], [:baz, 3]]
破解上述代码:
hash.group_by { |_,v| v }
# => {1=>[[:foo, 1]], 3=>[[:bar, 3], [:baz, 3]]}
hash.group_by { |_,v| v }.max_by { |k,_| k }
# => [3, [[:bar, 3], [:baz, 3]]]