Package g0301_0400.s0377_combination_sum_iv

Class Solution

  • All Implemented Interfaces:
    
public final class Solution

    377 - Combination Sum IV.

    Medium

    Given an array of distinct integers nums and a target integer target, return the number of possible combinations that add up to target.

    The test cases are generated so that the answer can fit in a 32-bit integer.

    Example 1:

    Input: nums = 1,2,3, target = 4

    Output: 7

    Explanation:

    The possible combination ways are:
(1, 1, 1, 1)
(1, 1, 2)
(1, 2, 1)
(1, 3)
(2, 1, 1)
(2, 2)
(3, 1)
Note that different sequences are counted as different combinations.

    Example 2:

    Input: nums = 9, target = 3

    Output: 0

    Constraints:

    • 1 <= nums.length <= 200

    • 1 <= nums[i] <= 1000

    • All the elements of nums are unique.

    • 1 <= target <= 1000

    Follow up: What if negative numbers are allowed in the given array? How does it change the problem? What limitation we need to add to the question to allow negative numbers?

    • 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 Integer combinationSum4(IntArray nums, Integer target)

      • Methods inherited from class java.lang.Object

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