Package g0001_0100.s0039_combination_sum

Class Solution

java.lang.Object
g0001_0100.s0039_combination_sum.Solution
public class Solution extends java.lang.Object
39 - Combination Sum.

Medium

Given an array of distinct integers candidates and a target integer target, return a list of all unique combinations of candidates where the chosen numbers sum to target. You may return the combinations in any order.

The same number may be chosen from candidates an unlimited number of times. Two combinations are unique if the frequency of at least one of the chosen numbers is different.

It is guaranteed that the number of unique combinations that sum up to target is less than 150 combinations for the given input.

Example 1:

Input: candidates = [2,3,6,7], target = 7

Output: [[2,2,3],[7]]

Explanation:

 2 and 3 are candidates, and 2 + 2 + 3 = 7. Note that 2 can be used multiple times.
 7 is a candidate, and 7 = 7.
 These are the only two combinations.

Example 2:

Input: candidates = [2,3,5], target = 8

Output: [[2,2,2,2],[2,3,3],[3,5]]

Example 3:

Input: candidates = [2], target = 1

Output: []

Example 4:

Input: candidates = [1], target = 1

Output: 1

Example 5:

Input: candidates = [1], target = 2

Output: 1,1

Constraints:

  • 1 <= candidates.length <= 30
  • 1 <= candidates[i] <= 200
  • All elements of candidates are distinct.
  • 1 <= target <= 500

  • Constructor Summary

    Constructors
    Constructor
    Description
    Solution()
     

  • Method Summary

    Modifier and Type
    Method
    Description
    java.util.List<java.util.List<java.lang.Integer>>
    combinationSum(int[] coins, int amount)
     

    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

    • combinationSum

      public java.util.List<java.util.List<java.lang.Integer>> combinationSum(int[] coins, int amount)