javascript - 在元素数组中查找重复的元素系列

Question

我有一个这样的数组

 var randomArray = [1,2,1,1,1,1,0,2,1,2,3,10,12,54,10,12] etc..

我可以删除重复元素或在其中找到重复元素。但我想记录数组中重复的所有重复元素序列。这是我试过的代码，但它会陷入无限循环

  for (i = 0; i < randomLength; i++) {
    var cycle = [i],
    flag = 0,
    start = i;
    for (var j = i + 1; j < randomLength; j++) {
       if (randomArray[i] == randomArray[j]) {
         cycle.push(randomArray[j]);
         while (i <= j) {
            if (randomArray[i + 1] == randomArray[j + 1]) {
                cycle.push(randomArray[j + 1]);
            }
            i = i + 1;
            j = j + 1;
         }
         console.log(cycle);
       }
       i = start;
    }
   i = start;
 }  

它应该返回我。我不想用正则表达式做同样的事情

1,2
1,1
10,12

If array is ["a","d","z","e","g","h","a","d","z"]  

然后

output would be "a","d","z"

而且应该是最优解。请就此建议我。至少更正我当前的代码..

Answer 1

我使用了“trie”树数据结构(用谷歌搜索了解更多信息)。 每个序列的树分支。 它找到 1,1,1 作为解决方案，因为 1,1,1 出现了两次。 (如果你想阻止一个数字在两个序列中重复，你需要计算 trie 的每个节点的唯一索引)。

这是代码:运行时间应该是 O(N^2) 之类的，可以稍微改进一下。

var randomArray = [1,2,1,1,1,1,0,2,1,2,3,10,12,54,10,12]

var solve = function(a) {
    var trie = {};
    var sequence_set = {};
    for (var start = 0; start < a.length - 1; start += 1)  {
        var sub_trie = trie[a[start]] || {};
        trie[a[start]] = sub_trie;
        sequence = "" + a[start]
        for (var i = start + 1; i < a.length; i += 1) {
            sequence += "," + a[i]
            sub_trie[a[i]] = sub_trie[a[i]] || {};
            sub_trie = sub_trie[a[i]];
            var sub_trie_count = sub_trie.count || 0;
            sub_trie.count = sub_trie_count + 1;
            if (sub_trie_count >= 1) {
                sequence_set[sequence] = "found";
                console.log(sequence);
            }
        }
    }
    solution = "";
    for (sequence in sequence_set) {
        solution += sequence + ", ";
    }
    console.log(trie)
    return solution;
}

输出:

1,1 fiddle.jshell.net:37
1,1,1 fiddle.jshell.net:37
1,1 fiddle.jshell.net:37
2,1 fiddle.jshell.net:37
1,2 fiddle.jshell.net:37
10,12 fiddle.jshell.net:37
Object {0: Object, 1: Object, 2: Object, 3: Object, 10: Object, 12: Object, 54: Object}
 fiddle.jshell.net:45