// bzoj4520#include<algorithm>#include<iostream>#include<cstdlib>#include<cstring>#include<cstdio>#include<vector>#include<cmath>#include<queue>#define LL long long#define inf 1<<30#define Pi acos(-1.0)#define free(a) freopen(a".in","r",stdin),freopen(a".out","w",stdout);using namespace std;const int maxn=100010;int n,m,D,K,rt;priority_queue<LL,vector<LL>,greater<LL> > q;struct KDtree {	int l,r,v[2],mn[2],mx[2];	friend bool operator < (const KDtree a,const KDtree b) {		return a.v[D]<b.v[D];	}}tr[maxn],S;void update(int k) {	for (int i=0;i<=1;i++) {		if (tr[k].l) {			tr[k].mn[i]=min(tr[k].mn[i],tr[tr[k].l].mn[i]);			tr[k].mx[i]=max(tr[k].mx[i],tr[tr[k].l].mx[i]);		}		if (tr[k].r) {			tr[k].mn[i]=min(tr[k].mn[i],tr[tr[k].r].mn[i]);			tr[k].mx[i]=max(tr[k].mx[i],tr[tr[k].r].mx[i]);		}	}}int build(int l,int r,int p) {	D=p;	int mid=(l+r)>>1;	nth_element(tr+l,tr+mid,tr+r+1);	if (l<mid) tr[mid].l=build(l,mid-1,p^1);	if (r>mid) tr[mid].r=build(mid+1,r,p^1);	update(mid);	return mid;}LL dis(LL x1,LL y1,LL x2,LL y2) {	return (x1-x2)*(x1-x2)+(y1-y2)*(y1-y2);}LL eva(int k) {    LL lu=dis(S.v[0],S.v[1],tr[k].mn[0],tr[k].mn[1]);    LL ru=dis(S.v[0],S.v[1],tr[k].mx[0],tr[k].mn[1]);    LL ld=dis(S.v[0],S.v[1],tr[k].mn[0],tr[k].mx[1]);    LL rd=dis(S.v[0],S.v[1],tr[k].mx[0],tr[k].mx[1]);    return max(max(lu,ru),max(ld,rd));}void query(int k) {	if (!k) return;	LL d=dis(S.v[0],S.v[1],tr[k].v[0],tr[k].v[1]);	if (q.top()<d) q.pop(),q.push(d);	LL dl=eva(tr[k].l),dr=eva(tr[k].r);	if (dl>dr) {		if (q.top()<dl) query(tr[k].l);		if (q.top()<dr) query(tr[k].r);	}	else {		if (q.top()<dr) query(tr[k].r);		if (q.top()<dl) query(tr[k].l);	}}	int main() {	scanf("%d%d",&n,&K);	for (int i=1;i<=n;i++) {		scanf("%d%d",&tr[i].v[0],&tr[i].v[1]);		tr[i].mn[0]=tr[i].mx[0]=tr[i].v[0];		tr[i].mn[1]=tr[i].mx[1]=tr[i].v[1];	}	rt=build(1,n,0);	for (int i=1;i<=2*K;i++) q.push(0);	for (int i=1;i<=n;i++) S=tr[i],query(rt);	printf("%lld",q.top());	return 0;}