/// Craciun Catalin
///  Elmaj
#include <fstream>
#include <iostream>

#define NMax 1000005

using namespace std;

ifstream f("elmaj.in");
ofstream g("elmaj.out");

long n;
long A[NMax];

long elmaj()
{
    int cand=-1, k=0;
    for (long i=1;i<=n;i++)
    {
        if (k==0)
        {
            cand=A[i];
            k++;
        }
        else if (cand==A[i])
            k++;
        else
            k--;
    }

    if (cand==-1)
        return -1;

    long nr=0;
    for (long i=1;i<=n;i++)
        if (A[i]==cand)
            nr++;

    if (nr>=n/2+1)
        return cand;
    else
        return -1;
}

void citire()
{
    f>>n;
    for (long i=1;i<=n;i++)
        f>>A[i];
    f.close();
}

int main()
{
    citire();

    g<<elmaj()<<'\n';
    g.close();

    return 0;
}