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Leetcode 674 Longest Continuous Increasing Subsequence

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

Example 1:

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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:

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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.

双整数储存信息

构造两个int, maxLength和currentLength, i从1遍历到nums.size() - 1, maxLength储存截止到现在最长的递增子序列长度, currentLength储存子数组nums[0]到nums[i]中包含nums[i]的最长的递增子序列长度. 若currentLength > maxLength, 则更新maxLength. O(n)

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class Solution {
public:
    int findLengthOfLCIS(vector<int>& nums) {
        if(nums.size() < 2)
            return nums.size();
        int maxLength = 1;
        int currentLength = 1;
        for(int i = 1; i < nums.size(); ++i)
        {
            if(nums[i] > nums[i - 1])
            {
                ++currentLength;
                if(currentLength > maxLength)
                    maxLength = currentLength;
            }
            else
            {
                currentLength = 1;
            }
        }
        return maxLength;
    }
};