Solution: Additive Number
Explore how to apply backtracking to solve the additive number problem, where digits form a sequence with each number as the sum of its two predecessors. Understand recursion depth, pruning strategies, and constraints like leading zeros. Gain the ability to implement this pattern for string partitioning problems in coding interviews.
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Statement
An additive number is a string whose digits can be partitioned into an additive sequence.
A valid additive sequence contains at least three numbers, where every number after the first two is equal to the sum of the two immediately preceding numbers.
Given a string, num, containing only digits, determine whether it represents an additive number. Return TRUE if a valid additive sequence can be formed from the digits of num, and FALSE otherwise.
Note: Numbers in the additive sequence cannot have leading zeros. For example, the sequences
1, 2, 03and1, 02, 3are both invalid.
Constraints:
num.length...