#include <bits/stdc++.h>
using namespace std;
const int dx[] = {1, 0, -1, 0};
const int dy[] = {0, -1, 0, 1};
const double EPS = 1e-9;
const int days[] = {31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};
const int daysleap[] = {31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};
int main() {
  int n, k;
  cin >> n >> k;
  vector<int> A(n);
  for (unsigned int i = 0; i < (n); i++) cin >> A[i];
  sort(A.begin(), A.end());
  vector<int> B = A;
  unique(B.begin(), B.end());
  reverse(B.begin(), B.end());
  vector<int> C = B;
  for (unsigned int i = 0; i < (B.size()); i++) {
    C[i] = count(A.begin(), A.end(), B[i]);
  }
  int kk = 0;
  for (unsigned int i = 0; i < (B.size()); i++) {
    kk += C[i];
    if (kk == k) {
      cout << B[i] << " " << B[i] << endl;
      return 0;
    }
  }
  cout << -1 << endl;
  return 0;
}
