#include <algorithm>
#include <cstring>
#include <iostream>
#include <queue>
using namespace std;
const int maxn = 100010;
long long n, k;
priority_queue<long long, vector<long long>, greater<long long> > q;

struct node {
  long long x, y;
} s[maxn];

bool cmp1(node a, node b) { return a.x < b.x; }

bool cmp2(node a, node b) { return a.y < b.y; }

long long lc[maxn], rc[maxn], L[maxn], R[maxn], D[maxn], U[maxn];

void maintain(int x) {
  L[x] = R[x] = s[x].x;
  D[x] = U[x] = s[x].y;
  if (lc[x])
    L[x] = min(L[x], L[lc[x]]), R[x] = max(R[x], R[lc[x]]),
    D[x] = min(D[x], D[lc[x]]), U[x] = max(U[x], U[lc[x]]);
  if (rc[x])
    L[x] = min(L[x], L[rc[x]]), R[x] = max(R[x], R[rc[x]]),
    D[x] = min(D[x], D[rc[x]]), U[x] = max(U[x], U[rc[x]]);
}

int build(int l, int r) {
  if (l > r) return 0;
  int mid = (l + r) >> 1;
  double av1 = 0, av2 = 0, va1 = 0, va2 = 0;  // average variance
  for (int i = l; i <= r; i++) av1 += s[i].x, av2 += s[i].y;
  av1 /= (r - l + 1);
  av2 /= (r - l + 1);
  for (int i = l; i <= r; i++)
    va1 += (av1 - s[i].x) * (av1 - s[i].x),
        va2 += (av2 - s[i].y) * (av2 - s[i].y);
  if (va1 > va2)
    nth_element(s + l, s + mid, s + r + 1, cmp1);
  else
    nth_element(s + l, s + mid, s + r + 1, cmp2);
  lc[mid] = build(l, mid - 1);
  rc[mid] = build(mid + 1, r);
  maintain(mid);
  return mid;
}

long long sq(long long x) { return x * x; }

long long dist(int a, int b) {
  return max(sq(s[a].x - L[b]), sq(s[a].x - R[b])) +
         max(sq(s[a].y - D[b]), sq(s[a].y - U[b]));
}

void query(int l, int r, int x) {
  if (l > r) return;
  int mid = (l + r) >> 1;
  long long t = sq(s[mid].x - s[x].x) + sq(s[mid].y - s[x].y);
  if (t > q.top()) q.pop(), q.push(t);
  long long distl = dist(x, lc[mid]), distr = dist(x, rc[mid]);
  if (distl > q.top() && distr > q.top()) {
    if (distl > distr) {
      query(l, mid - 1, x);
      if (distr > q.top()) query(mid + 1, r, x);
    } else {
      query(mid + 1, r, x);
      if (distl > q.top()) query(l, mid - 1, x);
    }
  } else {
    if (distl > q.top()) query(l, mid - 1, x);
    if (distr > q.top()) query(mid + 1, r, x);
  }
}

int main() {
  cin >> n >> k;
  k *= 2;
  for (int i = 1; i <= k; i++) q.push(0);
  for (int i = 1; i <= n; i++) cin >> s[i].x >> s[i].y;
  build(1, n);
  for (int i = 1; i <= n; i++) query(1, n, i);
  cout << q.top() << endl;
  return 0;
}