674. Longest Continuous Increasing Subsequence 最长连续递增序列

题目链接
tag:
-Easy；

• Sliding Window;

question
  Given an unsorted array of integers, find the length of longest continuous increasing subsequence (subarray).

Example 1:

Input: [1,3,5,4,7]
Output: 3
Explanation: The longest continuous increasing subsequence is [1,3,5], its length is 3.
Even though [1,3,5,7] is also an increasing subsequence, it's not a continuous one where 5 and 7 are separated by 4.

Example 2:

Input: [2,2,2,2,2]
Output: 1
Explanation: The longest continuous increasing subsequence is [2], its length is 1.

Note: Length of the array will not exceed 10,000.

思路：
  比较简单，滑动窗口，只要一个辅助变量当作窗口左边界，如果当前一个元素 num[i] 比 num[i-1] 大说明窗口增加，否者重新开始窗口。代码如下：

class Solution {
public:
    int findLengthOfLCIS(vector& nums) {
        // 滑动窗口
        if (nums.empty())
            return 0;
        if (nums.size() == 1)
            return 1;
        int res = 1, left = -1;
        for (int i=1; i nums[i-1])
                res = max(res, i-left);
            else
                left = i - 1;
        }
        return res;
    }
};