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class Solution {
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  public List<Integer> peopleIndexes(List<List<String>> favoriteCompanies) {
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    Set<String>[] fav = new Set[favoriteCompanies.size()];
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    Set<Integer> set = new HashSet<>();
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    for (int i = 0; i < favoriteCompanies.size(); i++) {
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      set.add(i);
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      fav[i] = new HashSet<>(favoriteCompanies.get(i));
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    }
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    for (int i = 1; i < favoriteCompanies.size(); i++) {
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      if (!set.contains(i)) continue;
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      for (int j = 0; j < i; j++) {
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        if (!set.contains(j)) continue;
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        if (isSubSet(fav[j], fav[i])) set.remove(j);
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        if (isSubSet(fav[i], fav[j])) set.remove(i);
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      }
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    }
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    List<Integer> ans = new ArrayList<>(set);
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    Collections.sort(ans);
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    return ans;
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  }
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  private boolean isSubSet(Set<String> child, Set<String> parent) {
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    if (child.size() > parent.size()) return false;
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    return parent.containsAll(child);
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  }
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}