Package g0301_0400.s0306_additive_number

Class Solution

  • All Implemented Interfaces:
    
public final class Solution

    306 - Additive Number\.

    Medium

    An additive number is a string whose digits can form an additive sequence.

    A valid additive sequence should contain at least three numbers. Except for the first two numbers, each subsequent number in the sequence must be the sum of the preceding two.

    Given a string containing only digits, return true if it is an additive number or false otherwise.

    Note: Numbers in the additive sequence cannot have leading zeros, so sequence 1, 2, 03 or 1, 02, 3 is invalid.

    Example 1:

    Input: "112358"

    Output: true

    Explanation: The digits can form an additive sequence: 1, 1, 2, 3, 5, 8. 1 + 1 = 2, 1 + 2 = 3, 2 + 3 = 5, 3 + 5 = 8

    Example 2:

    Input: "199100199"

    Output: true

    Explanation: The additive sequence is: 1, 99, 100, 199. 1 + 99 = 100, 99 + 100 = 199

    Constraints:

    • 1 <= num.length <= 35

    • num consists only of digits.

    Follow up: How would you handle overflow for very large input integers?

    • Nested Class Summary

      Nested Classes 
      Modifier and Type Class Description

    • Field Summary

      Fields 
      Modifier and Type Field Description

    • Constructor Summary

      Constructors 
      Constructor Description
      Solution()

    • Enum Constant Summary

      Enum Constants 
      Enum Constant Description

    • Method Summary

      Modifier and Type Method Description
      final Boolean isAdditiveNumber(String num)

      • Methods inherited from class java.lang.Object

        clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait