#include <iostream>
#include <list>
#include <string>
#include <algorithm>
using namespace std;
 
typedef list<string> List;
 
int main() {
    List lst{ string("a"), string("b"), string("c") };
    auto it = lst.begin();
    advance(it, 1);
 
    // _M_next->_M_prev = _M_prev; _M_prev->_M_next = _M_next;
    it._M_node->_M_unhook();
 
    delete static_cast<_List_node<string> *>(it._M_node);
 
    for (auto &s : lst)
        cout << s << endl;
}

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