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var smallestMissingValueSubtree = function (parents, nums) {
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  let n = parents.length,
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    next = [...Array(n)].map((d) => []),
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    used = {};
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  for (let i = 1; i < n; i++) next[parents[i]].push(i);
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  let dfs = (node) => {
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    if (used[nums[node]]) return;
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    used[nums[node]] = true;
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    for (let child of next[node]) dfs(child);
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  };
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  let cur = nums.indexOf(1),
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    leftAt = 1,
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    res = [...Array(n)].map((d) => 1);
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  while (cur !== -1) {
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    dfs(cur);
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    while (used[leftAt]) leftAt++;
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    res[cur] = leftAt;
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    cur = parents[cur];
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  }
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  return res;
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};