#include <bits/stdc++.h>
#include "grader.h"
using namespace std;
#define MASK(x) (1LL << (x))
#define BIT(x, i) (((x) >> (i)) & 1)
#define ALL(x) (x).begin(), (x).end()
#define REP(i, n) for (int i = 0, _n = n; i < _n; ++i)
#define FOR(i, a, b) for (int i = (a), _b = (b); i <= _b; ++i)
#define FORD(i, a, b) for (int i = (a), _b = (b); i >= _b; --i)
#define FORE(i, a, b) for (int i = (a), _b = (b); i < _b; ++i)
#define debug(...) "[" << #__VA_ARGS__ ": " << (__VA_ARGS__) << "] "
#define file(name) if (fopen(name".inp", "r")) { freopen(name".inp", "r", stdin); freopen(name".out", "w", stdout); }
template <class A, class B> bool minimize(A &a, B b) { if (a > b) { a = b; return true; } return false; }
template <class A, class B> bool maximize(A &a, B b) { if (a < b) { a = b; return true; } return false; }
mt19937 jdg(chrono::steady_clock::now().time_since_epoch().count());
long long Rand(long long l, long long r) { return l + jdg() % (r - l + 1); }
void solve(int N) {
srand(time(nullptr));
FOR(i, 1, min(N, 25)) {
int x = Rand(1, N);
x = kth(x);
if(cnt(x) > N / 3) {
say_answer(x);
return;
}
}
say_answer(-1);
}
#ifdef LOCAL
#include <bits/stdc++.h>
#include "grader.h"
using namespace std;
static const int MIN_VALUE = 0, MAX_VALUE = (1e9) - 1;
static map<int,int> mp;
static int Q, N, a[5005];
static bool issol, answer;
void solve(int N);
void say_answer(int k)
{
if(answer)
{
cout << "Multiple answers provided for the same testcase!\n";
exit(0);
}
answer = 1;
if(k == -1)
{
if(issol)
{
cout << "Wrong answer\n";
exit(0);
}
else cout << "Correct! Number of queries: " << Q << '\n';
}
else
{
if(!issol || mp[k] <= N/3)
{
cout << "Wrong answer\n";
exit(0);
}
else cout << "Correct! Number of queries: " << Q << '\n';
}
}
int cnt(int k)
{
++Q;
if(!(k>=MIN_VALUE && k<=MAX_VALUE))
{
cout << "Wrong query format\n";
exit(0);
}
return mp[k];
}
int kth(int k)
{
++Q;
if(!(k>=1 && k<=N))
{
cout << "Wrong query format\n";
exit(0);
}
return a[k];
}
int main()
{
freopen("TASK.inp", "r", stdin);
freopen("TASK.out", "w", stdout);
int tests, i;
cin >> tests;
while(tests--)
{
cin >> N; mp.clear();
Q = 0; issol = 0; answer = 0;
for(i=1; i<=N; ++i) cin >> a[i], ++mp[a[i]];
for(i=1; i<=N; ++i) issol |= (mp[a[i]] > N/3);
solve(N);
}
return 0;
}
#endif
// Dream it. Wish it. Do it.
