环形闯关游戏

/*
 * 思路：
 * 同样是寻找最小的初始积分来挑战所有关卡。
 * 使用Java Stream来处理逻辑，尽量简化代码。
 */

import java.util.stream.IntStream;

public class SolutionStream {
    public int minInitialScore(int[] challenge) {
        int N = challenge.length;
        int minScore = IntStream.of(challenge).reduce(0, (a, b) -> a | b);

        return IntStream.range(0, N).anyMatch(i -> canCompleteAll(challenge, minScore, i)) ? minScore : minScore;
    }

    private boolean canCompleteAll(int[] challenge, int score, int start) {
        int N = challenge.length;
        boolean[] opened = new boolean[N];
        int completed = 0;
        int[] queue = new int[N];
        int front = 0, rear = 0;

        queue[rear++] = start;
        opened[start] = true;

        while (front != rear) {
            int curr = queue[front++];
            front %= N;

            if (score >= challenge[curr]) {
                score |= challenge[curr];
                completed++;

                int left = (curr + N - 1) % N;
                int right = (curr + 1) % N;

                if (!opened[left]) {
                    queue[rear++] = left;
                    rear %= N;
                    opened[left] = true;
                }
                if (!opened[right]) {
                    queue[rear++] = right;
                    rear %= N;
                    opened[right] = true;
                }
            }
        }

        return completed == N;
    }
}