Given an array of strictly increasing positive integers arr, find the length of the longest Fibonacci like subsequence of arr. If no such subsequence exists, return $0$.

A sequence $x_1, x_2, \dots, x_k$ is considered Fibonacci like if:

• $k \geq 3$

• $x_i + x_{i+1} = x_{i+2}$ for all $1 \leq i \leq k - 2$

A subsequence is obtained by deleting zero or more elements from arr without altering the relative order of the remaining elements.

Constraints:

• $3 \leq$ arr.length $\leq 1000$

• $1 \leq$ arr[i] $<$ arr[i + 1] $\leq 10^9$

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