#include <iostream>
#include <fstream>
#include <cmath>
#include <set>
using namespace std;

int main(){
	ifstream in("tmp_26");

	int n;
	in >> n;
	cout << n << '\n';
	int a[5000];
	set<int> s;
	for (int i = 0; i < n; i++) {
		in >> a[i];
		s.insert(a[i]);
	}
	int counter = 0;
	int maxx = 0;
	for (int i = 0; i < n; i++) {
		for (int j = i + 1; j < n; j++) {
			if (a[i] % 2 == 0 || a[j] % 2 == 0) {
				continue;
			}
			int sr = (a[i] + a[j]) / 2;
			if (s.count(sr)) {
				cout << "URA\n";
				counter++;
				maxx = max(maxx, sr);
				break;
			}
		}
	}
	cout << counter << ' ' << maxx << '\n';
	in.close();
	return 0;
}