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feat: add ruby code block - heap sort (#1261)
* feat(codes/ruby/chapter_sorting/heap_sort.rb): add heap_sort ruby file * feat(codes/ruby/chapter_sorting/heap_sort.rb): modify comment space * feat(codes/ruby/chapter_sorting/heap_sort.rb): modify code space style * feat(codes/ruby/chapter_sorting/heap_sort.rb): modify logic instruction Co-authored-by: khoaxuantu <68913255+khoaxuantu@users.noreply.github.com> * feat(codes/ruby/chapter_sorting/heap_sort.rb): driver code add if logic Co-authored-by: khoaxuantu <68913255+khoaxuantu@users.noreply.github.com> --------- Co-authored-by: khoaxuantu <68913255+khoaxuantu@users.noreply.github.com>
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codes/ruby/chapter_sorting/heap_sort.rb
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codes/ruby/chapter_sorting/heap_sort.rb
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=begin
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File: heap_sort.rb
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Created Time: 2024-04-10
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Author: junminhong (junminhong1110@gmail.com)
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=end
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### 堆的长度为 n ,从节点 i 开始,从顶至底堆化 ###
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def sift_down(nums, n, i)
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while true
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# 判断节点 i, l, r 中值最大的节点,记为 ma
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l = 2 * i + 1
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r = 2 * i + 2
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ma = i
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ma = l if l < n && nums[l] > nums[ma]
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ma = r if r < n && nums[r] > nums[ma]
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# 若节点 i 最大或索引 l, r 越界,则无须继续堆化,跳出
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break if ma == i
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# 交换两节点
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nums[i], nums[ma] = nums[ma], nums[i]
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# 循环向下堆化
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i = ma
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end
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end
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### 堆排序 ###
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def heap_sort(nums)
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# 建堆操作:堆化除叶节点以外的其他所有节点
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(nums.length / 2 - 1).downto(0) do |i|
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sift_down(nums, nums.length, i)
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end
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# 从堆中提取最大元素,循环 n-1 轮
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(nums.length - 1).downto(1) do |i|
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# 交换根节点与最右叶节点(交换首元素与尾元素)
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nums[0], nums[i] = nums[i], nums[0]
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# 以根节点为起点,从顶至底进行堆化
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sift_down(nums, i, 0)
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end
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end
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### Driver Code ###
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if __FILE__ == $0
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nums = [4, 1, 3, 1, 5, 2]
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heap_sort(nums)
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puts "堆排序完成后 nums = #{nums.inspect}"
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end
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