0842. Split Array into Fibonacci Sequence

https://leetcode.com/problems/split-array-into-fibonacci-sequence

Description

You are given a string of digits num, such as "123456579". We can split it into a Fibonacci-like sequence [123, 456, 579].

Formally, a Fibonacci-like sequence is a list f of non-negative integers such that:

• 0 <= f[i] < 231, (that is, each integer fits in a 32-bit signed integer type),

• f.length >= 3, and

• f[i] + f[i + 1] == f[i + 2] for all 0 <= i < f.length - 2.

Note that when splitting the string into pieces, each piece must not have extra leading zeroes, except if the piece is the number 0 itself.

Return any Fibonacci-like sequence split from num, or return [] if it cannot be done.

Example 1:

**Input:** num = "123456579"
**Output:** [123,456,579]

Example 2:

**Input:** num = "11235813"
**Output:** [1,1,2,3,5,8,13]

Example 3:

**Input:** num = "112358130"
**Output:** []
**Explanation:** The task is impossible.

Example 4:

**Input:** num = "0123"
**Output:** []
**Explanation:** Leading zeroes are not allowed, so "01", "2", "3" is not valid.

Example 5:

**Input:** num = "1101111"
**Output:** [11,0,11,11]
**Explanation:** The output [11, 0, 11, 11] would also be accepted.

Constraints:

• 1 <= num.length <= 200

• num contains only digits.

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