#include <bits/stdc++.h>
using namespace std;
int n, m;
struct Point {
  int x, y;
  Point(int _x = 0, int _y = 0) { x = _x, y = _y; }
  friend Point operator-(const Point &a, const Point &b) {
    return Point(a.x - b.x, a.y - b.y);
  }
  friend long long operator%(const Point &a, const Point &b) {
    return 1LL * a.x * b.y - 1LL * a.y * b.x;
  }
} p[404];
long long Z;
bool check(long long z) {
  static pair<int, long long> dp[404][404];
  memset(dp, 0, sizeof(dp));
  for (int i = 1; i <= n * 2 - 2; ++i) {
    long long w = (p[i + 1] - p[i]) % (p[i + 2] - p[i]);
    dp[i][i + 2] = w >= z ? make_pair(1, 0LL) : make_pair(0, w);
    if (dp[i][i + 2].first >= m) return true;
  }
  for (int len = 4; len <= n + 1; ++len) {
    for (int l = 1; l + len - 1 <= 2 * n; ++l) {
      int r = l + len - 1;
      dp[l][r] = make_pair(0, 0LL);
      for (int k = l + 1; k < r; ++k) {
        auto t = make_pair(
            dp[l][k].first + dp[k][r].first,
            dp[l][k].second + dp[k][r].second + (p[k] - p[l]) % (p[r] - p[l]));
        if (t.second >= z) ++t.first, t.second = 0;
        if (t.first >= m) return true;
        dp[l][r] = max(dp[l][r], t);
      }
    }
  }
  return false;
}
int main() {
  ios::sync_with_stdio(false);
  cin.tie(0);
  cin >> n >> m;
  ++m;
  for (int i = 1; i <= n; ++i) {
    cin >> p[i].x >> p[i].y;
  }
  for (int i = 1; i <= n; ++i) {
    p[i + n] = p[i];
  }
  long long l = 1, r = 1e17 + 233, ans = 0;
  while (l < r) {
    long long mid = (l + r) >> 1;
    if (check(mid)) {
      ans = mid, l = mid + 1;
    } else {
      r = mid;
    }
  }
  cout << ans << '\n';
  return 0;
}
