从字符串数组生成唯一的初始字符串

Question

我有一长串字符串。例如：

["Abyssal Specter", "Air Elemental", "Aladdin's Ring", "Ambition's Cost", "Anaba Shaman", "Angel of Mercy", "Angelic Page", "Archivist", "Ardent Militia", "Avatar of Hope", "Aven Cloudchaser","Aven Fisher"]

现在，这个数组必须传递给一个应该返回的方法。

[["Abyssal Specter","Ab"], ["Air Elemental", "Ai"], ["Aladdin's Ring","Al"], ["Ambition's Cost","Am"], ["Anaba Shaman","Ana"], ["Angel of Mercy","Angel "], ["Angelic Page","Angeli"], ["Archivist","Arc"], ["Ardent Militia","Ard"], ["Avatar of Hope","Ava"], ["Aven Cloudchaser","Aven C"],["Aven Fisher","Aven F"]]

该方法应返回数组中每个字符串的唯一首字母。

例如，"Abyssal Specter"应该返回"Ab"，因为没有以"Ab"开头的其他字符串。同样，对于"Air Elemental"到"Ai"也是如此。但是"Aven Cloudchaser"应该返回"Aven C"，因为有一个字符串"Aven Fisher"。简而言之，它应该只生成唯一的字符串首字母。

Answer 1

Standard中的缩写就是这样做的：

require 'abbrev'

ar = ["Abyssal Specter", "Air Elemental", "Aladdin's Ring", "Ambition's Cost", "Anaba Shaman", "Angel of Mercy", "Angelic Page", "Archivist", "Ardent Militia", "Avatar of Hope", "Aven Cloudchaser","Aven Fisher"]
p ar.abbrev.invert.to_a

# [["Abyssal Specter", "Ab"], ["Air Elemental", "Ai"], ["Aladdin's Ring", "Al"], ["Ambition's Cost", "Am"], ["Anaba Shaman", "Ana"], ["Angel of Mercy", "Angel "], ["Angelic Page", "Angeli"], ["Archivist", "Arc"], ["Ardent Militia", "Ard"], ["Avatar of Hope", "Ava"], ["Aven Cloudchaser", "Aven C"], ["Aven Fisher", "Aven F"]]