Sep 7, 2022 · Sep 4, 2022 · Sep 4, 2022 · Sep 4, 2022 · Sep 7, 2022 · Sep 7, 2022
diff --git a/problems/0216.组合总和III.md b/problems/0216.组合总和III.md
Original file line number	Diff line number	Diff line change
Expand Up		@@ -260,6 +260,37 @@ class Solution {
		}
		}
		}

	// 上面剪枝 i <= 9 - (k - path.size()) + 1; 如果还是不清楚
	// 也可以改为 if (path.size() > k) return; 执行效率上是一样的
	class Solution {
	LinkedList<Integer> path = new LinkedList<>();
	List<List<Integer>> ans = new ArrayList<>();
	public List<List<Integer>> combinationSum3(int k, int n) {
	build(k, n, 1, 0);
	return ans;
	}

	private void build(int k, int n, int startIndex, int sum) {

	if (sum > n) return;

	if (path.size() > k) return;

	if (sum == n && path.size() == k) {
	ans.add(new ArrayList<>(path));
	return;
	}

	for(int i = startIndex; i <= 9; i++) {
	path.add(i);
	sum += i;
	build(k, n, i + 1, sum);
	sum -= i;
	path.removeLast();
	}
	}
	}
		```

		其他方法
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