从最后一个对象级别移动到第一个对象级别

I have such array of objects:

我有这样的对象数组：

var Categories = [
    {n:'1st category',u:1,s:[{n:'Sub category',u:2,s:[{n:'Sub sub category',u:3,s:[]},{n:'Sub sub category 2',u:4,s:[]},{n:'Sub sub category 3',u:5,s:[]}]},{n:'Sub category',u:6,s:[{n:'Sub sub category',u:7,s:[]},{n:'Sub sub category 2',u:8,s:[]},{n:'Sub sub category 3',u:9,s:[]}]},{n:'Sub category',u:10,s:[{n:'Sub sub category',u:11,s:[]},{n:'Sub sub category 2',u:12,s:[]},{n:'Sub sub category 3',u:13,s:[]}]}]},
    {n:'2nd category',u:14,s:[{n:'Sub category',u:15,s:[{n:'Sub sub category',u:16,s:[]},{n:'Sub sub category 2',u:17,s:[]},{n:'Sub sub category 3',u:18,s:[]}]}]},
    {n:'3rd category',u:19,s:[{n:'Sub category',u:20,s:[{n:'Sub sub category',u:21,s:[]},{n:'Sub sub category 2',u:22,s:[]},{n:'Sub sub category 3',u:23,s:[]}]}]}
];
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