Swift相交多个数组[关闭]

Question

我有一个数组数组

A = [[1,2,3], [2,4,6], [3,6,2,1],[1,1,1],..].

A的大小是动态的。我想在A中找到共同点。如何在Swift中实现？

Answer 1

给出数组的数组

let lists = [[1,2,3], [2, 3, 4], [3, 4, 5]]

您可以找到书写的常见元素let firstList = lists.first ?? []

let commonElements = lists.reduce(Set(firstList)) { (result, list)  in
    result.intersection(list)
}

结果print(commonElements) // [3]