you are a frog

V2EXJumpingFrog.java

class Solution {
    int solve (int[] staircase, int[] possible_steps) {
        int min_step = Integer.MAX_VALUE, N = staircase.length;
        for (int step : possible_steps)
            min_step = Math.min (min_step, step);
        if (min_step > N)
            return 0;
        int[] dp = new int[N];
        for (int i = -1 + min_step; i < N; i++) {
            int cur = Integer.MIN_VALUE;
            for (int step : possible_steps) {
                if (i - step >= -1)
                    cur = Math.max (cur, i - step >= 0 ? dp[i - step] : 0);
            }
            cur += staircase[i];
            for (int j = i; i - j < min_step; j--)
                cur = Math.max (cur, dp[j]);
            dp[i] = cur;
        }
        return dp[N - 1];
    }
}