如何在list的list中使用typedef？

#include <iostream>
#include <list>

typedef std::list<int> InnerList;
typedef std::list<InnerList> ListOfLists;

int main() {
    ListOfLists listOfLists;

    InnerList innerList1;
    innerList1.push_back(1);
    innerList1.push_back(2);
    innerList1.push_back(3);

    InnerList innerList2;
    innerList2.push_back(4);
    innerList2.push_back(5);
    innerList2.push_back(6);

    listOfLists.push_back(innerList1);
    listOfLists.push_back(innerList2);

    // 遍历list的list并输出元素
    for (const auto& innerList : listOfLists) {
        for (const auto& element : innerList) {
            std::cout << element << " ";
        }
        std::cout << std::endl;
    }

    return 0;
}