give array distinct integer candidate target integer target return list unique combination candidate choose number sum target you return combination orderthe number choose candidate unlimited number time two combination unique frequency choose number differentThe test case generate number unique combination sum target 150 combination give input Example 1input candidate 2367 target 7output 2237explanation2 3 candidate 2 2 3 7 note 2 multiple times7 candidate 7 7these combinationsExample 2input candidate 235 target 8Output 222223335example 3input candidate 2 target 1output Constraints1 candidateslength 302 candidatesi 40all element candidate distinct1 target 40