=..=：是这样吗？ vector<vector<int>>res; vector<int>temp; void find_all(vector<vector<int>>num,int index){ if (index == num.size()) res.push_back(temp); else{ for (int i = 0; i < num[index].size(); i++){ temp.push_back(num[index][i]); find_all(num, index + 1); temp.pop_back(); } } } int main() { vector<vector<int>>num = { { 1, 2, 8 }, { 2, 5, 6, 7 }, { 3 } }; find_all(num, 0); return 0; }