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class Solution {
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 public:
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  int f(int i, vector<int> &v, int a, int b) {
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    if (i == v.size()) {
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      if (a == b) {
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        return a;
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      }
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      return 0;
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    }
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    int x = f(i + 1, v, a, b);
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    int y = f(i + 1, v, a + v[i], b);
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    int z = f(i + 1, v, a, b + v[i]);
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    return max({x, y, z});
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  }
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  int tallestBillboard(vector<int> &rods) {
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    return f(0, rods, 0, 0);
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  }
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};