lintcode-easy-Longest Increasing Continuous Subsequence

Give an integer array，find the longest increasing continuous subsequence in this array.

An increasing continuous subsequence:

• Can be from right to left or from left to right.
• Indices of the integers in the subsequence should be continuous.

Example

For [5, 4, 2, 1, 3], the LICS is [5, 4, 2, 1], return 4.

For [5, 1, 2, 3, 4], the LICS is [1, 2, 3, 4], return 4.

Notice

O(n) time and O(1) extra space.

 

public class Solution {
    /**
     * @param A an array of Integer
     * @return  an integer
     */
    public int longestIncreasingContinuousSubsequence(int[] A) {
        // Write your code here
        if(A == null || A.length == 0)
            return 0;
        
        if(A.length == 1)
            return 1;
        
        int result = 1;
        int count = 1;
        
        for(int i = 1; i < A.length; i++){
            if(A[i] > A[i - 1])
                count++;
            else
                count = 1;
            if(count > result)
                result = count;
        }
        
        count = 1;
        
        for(int i = A.length - 2; i >= 0; i--){
            if(A[i] > A[i + 1])
                count++;
            else
                count = 1;
            if(count > result)
                result = count;
        }
        
        return result;
    }
}