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[[nodiscard]] double step(int const A, int const B,
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                          std::unordered_map<int, std::unordered_map<int, double>> &Memo) {
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  if (A <= 0) return B <= 0 ? 0.5 : 1.0;
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  if (B <= 0) return 0.0;
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  auto const AIt{Memo.find(A)};
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  if (Memo.cend() != AIt) {
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    auto const BIt{AIt->second.find(B)};
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    if (AIt->second.cend() != BIt) return BIt->second;
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  }
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  double M{step(A - 100, B, Memo)};
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  M += step(A - 75, B - 25, Memo);
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  M += step(A - 50, B - 50, Memo);
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  M += step(A - 25, B - 75, Memo);
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  return Memo[A][B] = 0.25 * M;
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}
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class Solution {
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 public:
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  double soupServings(int n) {
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    if (n > 4750) return 1;
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    std::unordered_map<int, std::unordered_map<int, double>> Memo{};
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    return step(n, n, Memo);
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  }
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};