#include <cstdio>
#include <cstring>
#include <iostream>
#include <algorithm>
#include <queue>
#define rep for(int i=0;i<=1;i++)
#define x2(_) ((_)*(_))
using namespace std;
const int maxn=100010;
typedef long long ll;
struct kd
{
	 ll v[2],sm[2],sn[2];
	 int ls,rs;
	 ll & operator [] (int a) {return v[a];}
	 kd (){}
	 kd (ll a,ll b){v[0]=sm[0]=sn[0]=a,v[1]=sm[1]=sn[1]=b,ls=rs=0;}
}t[maxn];
priority_queue<ll> pq;
int n,m,D,root,now;
ll A,B;
bool cmp(kd a,kd b)
{
	return (a[D]==b[D])?(a[D^1]<b[D^1]):(a[D]<b[D]);
}
void pushup(int x,int y)
{
	rep t[x].sm[i]=max(t[x].sm[i],t[y].sm[i]),t[x].sn[i]=min(t[x].sn[i],t[y].sn[i]);
}
int rd()
{
	int ret=0,f=1;	char gc=getchar();
	while(gc<‘0‘||gc>‘9‘)	{if(gc==‘-‘)f=-f;	gc=getchar();}
	while(gc>=‘0‘&&gc<=‘9‘)	ret=ret*10+gc-‘0‘,gc=getchar();
	return ret*f;
}
int build(int l,int r,int d)
{
	if(l>r)	return 0;
	int mid=l+r>>1;
	D=d,nth_element(t+l,t+mid,t+r+1,cmp);
	t[mid].ls=build(l,mid-1,d^1),t[mid].rs=build(mid+1,r,d^1);
	if(t[mid].ls)	pushup(mid,t[mid].ls);
	if(t[mid].rs)	pushup(mid,t[mid].rs);
	return mid;
}
ll getdis(int x)
{
	return max(x2(t[x].sm[0]-A),x2(t[x].sn[0]-A))+max(x2(t[x].sm[1]-B),x2(t[x].sn[1]-B));
}
void query(int x)
{
	if(!x||getdis(x)<=-pq.top())	return ;
	if(x!=now&&x2(t[x][0]-A)+x2(t[x][1]-B)>-pq.top())	pq.push(-x2(t[x][0]-A)-x2(t[x][1]-B)),pq.pop();
	if(getdis(t[x].ls)>getdis(t[x].rs))	query(t[x].ls),query(t[x].rs);
	else	query(t[x].rs),query(t[x].ls);
}
int main()
{
	n=rd(),m=rd();
	int i,a,b;
	for(i=1;i<=n;i++)	a=rd(),b=rd(),t[i]=kd(a,b);
	for(i=1;i<=2*m;i++)	pq.push(0);
	root=build(1,n,0);
	for(i=1;i<=n;i++)	now=i,A=t[i].v[0],B=t[i].v[1],query(root);
	printf("%lld\n",-pq.top());
	return 0;
}