  Learn Tech Skills from Scratch @ Scaler EDGE # Longest Increasing Subsequence

Find the longest increasing subsequence of a given array of integers, A.

In other words, find a subsequence of array in which the subsequence’s elements are in strictly increasing order, and in which the subsequence is as long as possible.
This subsequence is not necessarily contiguous, or unique.
In this case, we only care about the length of the longest increasing subsequence.

Input Format:

``````The first and the only argument is an integer array A.
``````

Output Format:

``````Return an integer representing the length of the longest increasing subsequence.
``````

Constraints:

``````1 <= length(A) <= 2500
1 <= A[i] <= 2000
``````

Example :

``````Input 1:
A = [1, 2, 1, 5]

Output 1:
3

Explanation 1:
The sequence : [1, 2, 5]

Input 2:
A = [0, 8, 4, 12, 2, 10, 6, 14, 1, 9, 5, 13, 3, 11, 7, 15]

Output 2:
6

Explanation 2:
The sequence : [0, 2, 6, 9, 13, 15] or [0, 4, 6, 9, 11, 15] or [0, 4, 6, 9, 13, 15]
``````
NOTE: You only need to implement the given function. Do not read input, instead use the arguments to the function. Do not print the output, instead return values as specified. Still have a doubt? Checkout Sample Codes for more details. Hints
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