Question

我想将迭代中的当前元素与数组中的其余元素进行比较。从起点我没有问题。当我想要将当前元素与数组中背后的元素进行比较时，问题就出现了。

array = [1, 2, 3, 2, 3, 4, 5] array.each_with_index do |num, index| break if array[index + 1] == nil if num > array[index + 1] puts "#{num} is greater than the #{array[index + 1]}!" else puts "#{num} is less than the #{array[index + 1]}!" end end

我正在寻找类似的东西：

"3 is greater than 1 and 2 but less than 4 and 5"

有什么想法吗？

Answer 1

我假设您希望比较数组中的所有元素，因此您可以通过使用Array#select来执行以下操作：

array = [1, 2, 3, 2, 3, 4, 5]
filtered_array = array.uniq

array.each do |i|
  greater_than = filtered_array.select { |comp| comp < i }
  less_than = filtered_array.select { |comp| comp > i }

  puts "#{i} is greater than #{greater_than} but less than #{less_than}"
end

您可以使用格式化输出，但这会给出：

1 is greater than [] but less than [2, 3, 4, 5]
2 is greater than [1] but less than [3, 4, 5]
3 is greater than [1, 2] but less than [4, 5]
2 is greater than [1] but less than [3, 4, 5]
3 is greater than [1, 2] but less than [4, 5]
4 is greater than [1, 2, 3] but less than [5]
5 is greater than [1, 2, 3, 4] but less than []

Answer 2

partition个分组将元素分成两个独立的组。

array = [1,2,3,4,5]
array.each do |n|
  less_than, greater_than = *(array - [n]).partition { |m| m <= n }
  text = []
  text << "is greater than #{less_than.join(', ')}" if less_than.count > 0
  text << "is less than #{greater_than.join(', ')}" if greater_than.count > 0
  puts "#{n} #{text.join(' and ')}"
end

Answer 3

arr = [1, 2, 3, 2, 3, 4, 5]

a = arr.uniq.sort
  #=> [1, 2, 3, 4, 5] 
h = a.each_with_index.to_h
  #=> {1=>0, 2=>1, 3=>2, 4=>3, 5=>4} 

arr.each { |i| puts "#{i} is greater than #{a[0,h[i]]} but less than #{a[h[i]+1..-1]}" }

打印

1 is greater than [] but less than [2, 3, 4, 5]
2 is greater than [1] but less than [3, 4, 5]
3 is greater than [1, 2] but less than [4, 5]
2 is greater than [1] but less than [3, 4, 5]
3 is greater than [1, 2] but less than [4, 5]
4 is greater than [1, 2, 3] but less than [5]
5 is greater than [1, 2, 3, 4] but less than []

将当前元素与Array中的剩余元素进行比较（Ruby）

3 个答案: