算法——山脉序列中的最大值

描述
给 n 个整数的山脉数组，即先增后减的序列，找到山顶（最大值）
您在真实的面试中是否遇到过这个题？
样例
例1:
输入: nums = [1, 2, 4, 8, 6, 3]
输出: 8
例2:
输入: nums = [10, 9, 8, 7],
输出: 10

实现：

public class Solution {
    /**
     * @param nums: a mountain sequence which increase firstly and then decrease
     * @return: then mountain top
     */
    public int mountainSequence(int[] nums) {
        // write your code here
        
          if (nums == null || nums.length == 0) {
            return -1;
        }

        int start = 0;
        int end = nums.length - 1;
        while (start + 1 < end) {
            int mid = start + (end - start) / 2;
            if (nums[mid] > nums[mid - 1]) {
                start = mid;
            }
            if (nums[mid] > nums[mid + 1]) {
                end = mid;
            }
        }
        return Math.max(nums[start], nums[end]);
    }
}