3211. 生成不含相邻零的二进制字符串

题目链接：3211. 生成不含相邻零的二进制字符串

代码如下：

class Solution 
{
public:
	vector<string> validStrings(int n)
	{
		vector<string> res;
		string path(n, 0);

		auto dfs = [&](auto&& dfs, int i)->void
			{
				if (i == n)
				{
					res.push_back(path);
					return;
				}

				//填1
				path[i] = '1';
				dfs(dfs, i + 1);

				//填0
				if (i == 0 || path[i - 1] == '1')
				{
					path[i] = '0';//直接覆盖
					dfs(dfs, i + 1);
				}
			};

		dfs(dfs, 0);
		return res;
	}
};