@@ -0,0 +1,827 @@
+import java.util.List;%0Aimport java.util.ArrayList;%0A%0Aclass Solution %7B%0A    public List%3CList%3CInteger%3E%3E combinationSum3(int k, int n) %7B%0A        List%3CList%3CInteger%3E%3E result = new ArrayList%3C%3E();%0A        backTrack(k, n, 1, new ArrayList%3C%3E(), result);%0A        return result;%0A    %7D%0A%0A    private void backTrack(int k, int remain, int start, List%3CInteger%3E tempList, List%3CList%3CInteger%3E%3E result) %7B%0A        if (tempList.size() %3E k) %7B%0A            return;%0A        %7D%0A        if (tempList.size() == k && remain == 0) %7B%0A            result.add(new ArrayList%3CInteger%3E(tempList));%0A            return;%0A        %7D else %7B%0A            for (int i = start; i %3C= 9; i++) %7B%0A                tempList.add(i);%0A                backTrack(k, remain - i, i + 1, tempList, result);%0A                tempList.remove(tempList.size() - 1);%0A            %7D%0A        %7D%0A    %7D%0A%7D

216. Combination Sum III