#include <iostream>
#include <string>
#include <ctime>
#include <cstdlib>
using namespace std;
int main(){
    int n, active, s = 0;
    bool kek = true;
    cin >> n;
    string *str = new string[n];
    for (int i = 0; i < n; i++)
    {
        cin >> str[i];
    }
    for (int i = 0; i < n; i++)
    {
        for (int j = 0; j < n; j++)
        {
            if (str[i] == str[j] && i != j){
                str[j] = "1";
                s = 1;
            }

        }
        if (s == 1 && str[i]!="1"){
            cout << str[i] << endl;
        }

        str[i] = "1";
        s = 0;



    }
}

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