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

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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. 
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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.

Solution:

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class Solution {
    public int findLengthOfLCIS(int[] nums) {
            int ans = 0;
        int anchor = 0;
        
        for (int i = 0; i < nums.length; i++) {
            if (i > 0 && nums[i - 1] >= nums[i]) anchor = i;
            
            ans = Math.max(ans, i - anchor + 1);
            System.out.printf("i %d anchor %d %n", i, anchor);
        }
        
        return ans;
        
    }
}

Solution 2021-10-26

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class Solution {
    public int findLengthOfLCIS(int[] nums) {
        int[] dp = new int[nums.length];
        
        Arrays.fill(dp, 1);
        
        int max = 1;
        for (int i = 1; i < nums.length; i++) {
            if (nums[i] > nums[i - 1]) {
                dp[i] = Math.max(dp[i - 1] + 1, dp[i]);
            } 
            max = Math.max(dp[i], max);
        }
        
        return max;
    }
}