Minimum Difficulty of a Job Schedule

class Solution:
    def minDifficulty(self, jobDifficulty: List[int], d: int) -> int:

        if len(jobDifficulty) < d: return -1
        n = len(jobDifficulty)

        @lru_cache(None)
        def dp(cur_difficulty, i, d):
            if d == 1: return max(jobDifficulty[i:])
            if i == n-1: return inf

            cur_difficulty = max(cur_difficulty, jobDifficulty[i])

            change = cur_difficulty + dp(jobDifficulty[i+1], i+1, d-1)
            dont = dp(cur_difficulty, i+1, d)

            return min(change, dont)

        return dp(jobDifficulty[0], 0, d)