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class Solution {
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 public:
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  vector<int> earliestAndLatest(int n, int first, int second) {
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    int minRound = INT_MAX, maxRound = INT_MIN;
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    function<void(int, int, int, int)> dfs = [&](int deadMask, int i, int j, int curRound) {
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      while (i < j and deadMask & (1 << i)) // 'i' is dead warrior, try next
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        i += 1;
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      while (i < j and deadMask & (1 << j)) // 'j' is dead warrior, try next
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        j -= 1;
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      if (i >= j) // end of round, no more fights possible
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        dfs(deadMask, 1, n, curRound + 1);
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      else if (i == first and j == second) // BATTLE OF THE IMMORTALS
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        minRound = min(curRound, minRound), maxRound = max(curRound, maxRound);
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      else {                            // BATTLE includes a mortal
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        if (i != first and i != second) // 'i' is MORTAL, he may die
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          dfs(deadMask | (1 << i), i + 1, j - 1, curRound);
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        if (j != first and j != second) // 'j' is MORTAL, he may die
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          dfs(deadMask | (1 << j), i + 1, j - 1, curRound);
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      }
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    };
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    dfs(0, 1, n, 1);
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    return {minRound, maxRound};
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  }
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};