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# Length of Longest Subsequence

Problem Setter: mayank111 Problem Tester: glowing_glare

Problem Description

Given a 1D integer array A of length N, find the length of the longest subsequence which is first increasing (strictly) and then decreasing (strictly).

Problem Constraints

0 <= N <= 3000

-107 <= A[i] <= 107

Input Format

The first and the only argument contains an integer array A.

Output Format

Return an integer representing the answer as described in the problem statement.

Example Input

Input 1:

``` A = [1, 2, 1]
```

Input 2:

``` A = [1, 11, 2, 10, 4, 5, 2, 1]
```

Example Output

Output 1:

``` 3
```

Output 2:

``` 6
```

Example Explanation

Explanation 1:

``` [1, 2, 1] is the longest subsequence.
```

Explanation 2:

``` [1 2 10 4 2 1] is the longest subsequence.
```

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 question? Checkout Sample Codes for more details.
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