Solution.py

class Solution:
    def soupServings(self, n: int) -> float:
        @cache
        def dfs(i: int, j: int) -> float:
            if i <= 0 and j <= 0:
                return 0.5
            if i <= 0:
                return 1
            if j <= 0:
                return 0
            return 0.25 * (
                dfs(i - 4, j)
                + dfs(i - 3, j - 1)
                + dfs(i - 2, j - 2)
                + dfs(i - 1, j - 3)
            )

        return 1 if n > 4800 else dfs((n + 24) // 25, (n + 24) // 25)