【leetcode】908.最小差值 I

假设最大值max与最小值min之差为 diff
diff <= 2k 的时候，那么 res = 0
diff > 2k 的时候，那么 res = diff - 2k

var smallestRangeI = function (nums, k) {
    let min = Math.min(...nums)
    let max = Math.max(...nums)
    return max - min > 2 * k ? max - min - 2 * k : 0
};