#include <bits/stdc++.h>
using namespace std;
const int tinf = (int)1e9 + 7;
const long long inf = (long long)1e18 + 7;
const int N = 1e3 + 5;
int main() {
  {
    ios::sync_with_stdio(false);
    cin.tie(0);
    cout.tie(0);
  }
  long long n, k;
  cin >> n >> k;
  long long a[n], Min = inf, Max = -inf;
  for (int i = 0; i < n; i++)
    cin >> a[i], Min = min(Min, a[i]), Max = max(Max, a[i]);
  if (k == 1)
    cout << Min;
  else if (k == 2)
    cout << max(a[0], a[n - 1]);
  else if (k >= 3)
    cout << Max;
  else
    cout << Min;
}
