#include <fstream>
#include <unordered_map>

using namespace std;

ifstream fin("elmaj.in");
ofstream fout("elmaj.out");

unordered_map<int, int> m;
int n, x;

int main() {
    fin >> n;
    for(int i = 1; i <= n; i++) {
        fin >> x;
        m[x]++;
    }
    fin.close();
    int majoritar = -1;
    unordered_map<int, int>::iterator itr;
    for(itr = m.begin(); itr != m.end(); itr++) {
        if(itr -> second > n / 2) {
            majoritar = itr -> first;
            break;
        }
    }
    fout << majoritar;
    fout.close();
    return 0;
}