在Ruby中比较数组并删除重复项？

Question

比较多个数组并删除重复数据的最简单方法是什么？

所以(在这种情况下数组里面的数组)......

a = [[2, 1], [3, 3], [7, 2], [5, 6]]  
b = [[2, 1], [6, 7], [9, 9], [4, 3]]  
c = [[2, 1], [1, 1], [2, 2], [9, 9]]  
d = [[2, 1], [9, 9], [2, 2], [3, 1]]  

......会出来(优先考虑数组a,然后是b,然后是c,然后是d)

a = [[2, 1], [3, 3], [7, 2], [5, 6]]  
b = [[6, 7], [9, 9], [4, 3]]  
c = [[1, 1], [2, 2]]  
d = [[3, 1]]  

Answer 1

它只是设置差异或减法,你可以这样写.运算符重载可以是一个幸福:)

a 它是什么.

a
[[2, 1], [3, 3], [7, 2], [5, 6]]

b = b - a
[[6, 7], [9, 9], [4, 3]]

c = c - b - a # or c - (a + b)
[[1, 1], [2, 2]]

d = d - c - b - a # or d - (a + b + c)
[[3, 1]]