let nums = [6, 2, 8, 3, 5, 2, 4, 3, 7, 6];
var bestRotation = function(nums) {
    let space = []; //因为盖提需要在一个下表范围内的元素一起加1，利用差分数组降低时间复杂度
    let low, high;
    let current = 0;
    let max = 0,
        result = 0;
    space.length = nums.length + 1;
    for (let i = 0; i < nums.length; i++) {
        low = (i + 1) % 5;
        high = (i - nums[i] + nums.length + 1) % nums.length;
        if (!space[low])
            space[low] = 1;
        else
            space[low]++;
        if (!space[high])
            space[high] = -1;
        else
            space[high]--;
        if (low >= high) {
            if (!space[0])
                space[0] = 1;
            else
                space[0]++;
        }
    }
    for (let i = 0; i < space.length; i++) {
        if (space[i] != undefined)
            current += space[i];
        if (current > max) {
            max = current;
            result = i;
        }
    }
    return result;
};

console.log(bestRotation(nums));