红宝石：如何找到和阵列返回重复值？ [英] Ruby: How to find and return a duplicate value in array?

问题描述

改编是一个字符串数组，例如： [你好，世界，堆栈，溢出，你好 又] 。

什么是检查改编有重复的，如果是，返回他们中的一个（无论哪个）轻松优雅的方式。

例如：

  [A，B，C，B，A]＃=＆GT; A或B
[A，B，C]＃=＆GT;零
 

解决方案

  A = [A，B，C，B，A]
a.detect {| E | a.count（E）＆GT; 1}
 

arr is array of strings, e.g.: ["hello", "world", "stack", "overflow", "hello", "again"].

What would be easy and elegant way to check if arr has duplicates, and if yes, return one of them (no matter which).

Examples:

["A", "B", "C", "B", "A"]    # => "A" or "B"
["A", "B", "C"]              # => nil

解决方案

a = ["A", "B", "C", "B", "A"]
a.detect{ |e| a.count(e) > 1 }

这篇关于红宝石：如何找到和阵列返回重复值？的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！