1335.java

class Solution {
    public int minDifficulty(int[] jobDifficulty, int d) {
        int n = jobDifficulty.length;
        if (n < d) return -1;
        
        int[] dp = new int[n + 1];
        for (int i = n - 1; i >= 0; i--) {
            dp[i] = Math.max(dp[i + 1], jobDifficulty[i]);
        }
        
        for (int t = 1; t <= d; t++) {
            for (int i = 0; i <= n - t; i++) {
                int m = 0; dp[i] = 10010;
                for (int j = i; j <= n - t; j++) {
                    m = Math.max(m, jobDifficulty[j]);
                    dp[i] = Math.min(dp[i], m + dp[j + 1]);
                }
            }
        }
        return dp[0];
    }
}