Find the Town Judge LeetCode solution in JavaScript

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var findJudge = function (n, trust) {
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  const length = trust.length;
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  let possibleJudge = [],
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    judgeMap = new Map(),
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    value,
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    judge = -1;
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  for (let i = 0; i < length; i++) {
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    if (judgeMap.has(trust[i][0])) {
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      value = judgeMap.get(trust[i][0]);
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      value.push(trust[i][1]);
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      judgeMap.set(trust[i][0], value);
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    } else {
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      judgeMap.set(trust[i][0], [trust[i][1]]);
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    }
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  }
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  value = [];
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  for (let i = 1; i <= n; i++) {
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    if (!judgeMap.has(i)) {
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      possibleJudge.push(i);
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    } else {
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      value.push([i, judgeMap.get(i)]);
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    }
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  }
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  if (!value.length || value.length !== n - 1) {
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    if (possibleJudge.length === 1) return possibleJudge[0];
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    return judge;
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  }
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  for (let i = 0; i < possibleJudge.length; i++) {
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    judge = possibleJudge[i];
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    for (let j = 0; j < value.length; j++) {
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      if (value[j][1].indexOf(judge) < 0) {
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        judge = -1;
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        break;
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      }
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    }
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    if (judge !== -1) break;
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  }
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  return judge;
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};