849. Maximize Distance to Closest Person 

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class Solution {
    public int maxDistToClosest(int[] seats) {
        int maxDist = 1;

        int[] left = new int[seats.length]; // 左侧（不含当前座位）最接近的有人的座位的索引
        int[] right = new int[seats.length]; // 右侧（不含当前座位）最接近的有人的座位的索引

        int seatIndex = -1;
        for (int i = 0; i < seats.length; i++) {
            left[i] = seatIndex;
            if (seats[i] == 1) {
                seatIndex = i;
            }
        }
        seatIndex = -1;
        for (int i = seats.length - 1; i >= 0; i--) {
            right[i] = seatIndex;
            if (seats[i] == 1) {
                seatIndex = i;
            }
        }

        for (int i = 0; i < seats.length; i++) {
            if (seats[i] == 1) {
                continue;
            }
            if (left[i] != -1 && right[i] != -1) {
                maxDist = Math.max(maxDist, Math.min(i - left[i], right[i] - i));
            } else if (left[i] != -1) {
                maxDist = Math.max(maxDist, i - left[i]);

            } else if (right[i] != -1) {
                maxDist = Math.max(maxDist, right[i] - i);
            }
        }

        return maxDist;
    }
}

References

849. Maximize Distance to Closest Person