如何获得数组序列？ [关闭]

Question

我正在尝试验证我的用户的最后一条消息，并验证他是否在我的应用程序中使用 selfbot。

var array = ["a", "b", "c", "f", "b", "a", "b", "c", "f", "b", "a", "b", "c", "f", "b", "a", "b", "c", "f", "b", "a", "b", "c", "f", "b"];

// ["a", "b", "c", "f", "b"] is the sequency, selfbot detected?

我试过用这个，但我现在不知道如何继续

var array = ["a", "b", "c", "f", "b", "a", "b", "c", "f", "b", "a", "b", "c", "f", "b", "a", "b", "c", "f", "b", "a", "b", "c", "f", "b"];

let counts = {};
array.forEach(x => { counts[x] = (counts[x] || 0) + 1; });
console.log(counts);

Answer 1

一种方法是一一检查（也许不是最有效的）：

var sequence = ["a", "b", "c", "f", "b"]; // Sequence that shows whether user is bot

// Test cases
var array1 = ["a", "b", "c", "f", "b", "a", "b", "c", "f", "b", "a", "b", "c", "f", "b", "a", "b", "c", "f", "b", "a", "b", "c", "f", "b"];
var array2 = ["b", "a", "b", "b", "f", "c", "a", "b", "c", "d", "e", "f", "a", "f", "c", "c", "c", "c", "f", "a", "a", "b", "b", "e", "e"];

function selfBotDetector(arr, seq) {
  // Function to check if sequence matches given range
  var check = start => {
    for(var t = start; t < seq.length + start; t++) {
      if(arr[t] !== seq[t - start]) {
        return false;
      }
    }
    return true;
  };
  for (var i = 0; i < arr.length; i++) {
    var result = check(i);
    // If at any time the sequence matches return true
    if(result)
      return true;
  }
  // if true was never returned then the sequence did not match
  return false;
}

console.log("Array 1:", selfBotDetector(array1, sequence) ? "Selfbot detected" : "OK");
console.log("Array 2:", selfBotDetector(array2, sequence) ? "Selfbot detected" : "OK");

Answer 2

您可以像这样使用递归循环：

/*<ignore>*/console.config({maximize:true,timeStamps:false,autoScroll:false});/*</ignore>*/
const array = [
  'a',
  'b',
  'c',
  'f',
  'b',
  'a',
  'b',
  'c',
  'f',
  'b',
  'a',
  'b',
  'c',
  'f',
  'b',
  'a',
  'b',
  'c',
  'f',
  'b',
  'a',
  'b',
  'c',
  'f',
  'b',
];

let num = 0;
(function findSeq(seqStart = 0, seqEnd = 0, i = 0, j = -1) {
  while (++i < array.length && array[i] !== array[seqStart]);
  seqEnd = i;
  while (++j < seqEnd && array[i++] === array[j]);
  if (seqEnd === j)
    console.log(
      `Sequence ${++num} found between`,
      seqStart,
      seqEnd,
      array.slice(seqStart, seqEnd)
    );
  if (i < array.length) findSeq(seqEnd, 0, i - 1, j - 1);
})();
console.log(`${num} sequences found`);

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