Package g0301_0400.s0377_combination_sum_iv

Class Solution

java.lang.Object
g0301_0400.s0377_combination_sum_iv.Solution
public class Solution extends java.lang.Object
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?

  • Constructor Summary

    Constructors
    Constructor
    Description
    Solution()
     

  • Method Summary

    Modifier and Type
    Method
    Description
    int
    combinationSum4(int[] nums, int target)
     

    Methods inherited from class java.lang.Object

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

  • Constructor Details

    • Solution

      public Solution()

  • Method Details

    • combinationSum4

      public int combinationSum4(int[] nums, int target)