//#pragma GCC optimize("Ofast,unroll-loops,O3")
//#pragma GCC optimize("avx,avx2,sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,fma,tune=native")
#include<bits/stdc++.h>
//#include<bits/extc++.h>
//#pragma pack(1)
#define fast ios::sync_with_stdio(0); cin.tie(0);
#define int long long
#define pii pair<int,int>
#define x first
#define y second
#define N 200015
using namespace std;
//using namespace __gnu_pbds;
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
//typedef tree<int, null_type,less_equal<int>, rb_tree_tag,tree_order_statistics_node_update> order_multiset;
//typedef tree<int, null_type,less<int>, rb_tree_tag,tree_order_statistics_node_update> order_set;
int n,m,ans=-1e18;
pii arr[N];
struct Node{
int lch,rch,sum,cnt;
void pull(Node a,Node b){
sum=a.sum+b.sum;
cnt=a.cnt+b.cnt;
}
Node(int a=0,int b=0,int c=0,int d=0):lch(a),rch(b),sum(c),cnt(d){}
};
struct lisan{
vector<int>vt;
void in(int x){ vt.push_back(x); }
void build(){
sort(vt.begin(),vt.end());
vt.resize(unique(vt.begin(),vt.end())-vt.begin());
}
int idx(int x){ return upper_bound(vt.begin(),vt.end(),x)-vt.begin(); }
int val(int p){ return vt[p-1]; }
}uni;
struct segtree{
int num=1;
Node seg[32*N];
int add(int l,int r,int i,int pos,int c){
num++; seg[num]=seg[i];
if (l==r){
seg[num].cnt++;
seg[num].sum+=uni.val(l);
return num;
}
int mid=(l+r)>>1,j=num;
if (pos<=mid) seg[j].lch=add(l,mid,seg[i].lch,pos,c);
else seg[j].rch=add(mid+1,r,seg[i].rch,pos,c);
seg[j].pull(seg[seg[j].lch],seg[seg[j].rch]);
return j;
}
int query_pos(int l,int r,int i,int j,int k){
if (l==r) return l;
int mid=(l+r)>>1,rc1=seg[i].rch,rc2=seg[j].rch;
int right_have=seg[rc2].cnt-seg[rc1].cnt;
if (right_have>=k) return query_pos(mid+1,r,rc1,rc2,k);
else return query_pos(l,mid,seg[i].lch,seg[j].lch,k-right_have);
}
Node query(int l,int r,int i,int j,int ll,int rr){
// seg[j]-seg[i];
if (ll<=l&&rr>=r) return Node(0,0,seg[j].sum-seg[i].sum,seg[j].cnt-seg[i].cnt);
int mid=(l+r)>>1;
if (rr<=mid) return query(l,mid,seg[i].lch,seg[j].lch,ll,rr);
else if (ll>mid) return query(mid+1,r,seg[i].rch,seg[j].rch,ll,rr);
else {
Node q1=query(l,mid,seg[i].lch,seg[j].lch,ll,rr);
Node q2=query(mid+1,r,seg[i].rch,seg[j].rch,ll,rr);
Node ans=Node(); ans.pull(q1,q2);
return ans;
}
}
}seg;
int root[N];
int Query(int l,int r){
int p=seg.query_pos(1,n,root[l-1],root[r],m),val=uni.val(p);
Node now=seg.query(1,n,root[l-1],root[r],p,n);
if (now.cnt>m){
now.sum=(now.sum-(now.cnt-m)*val);
now.sum=m;
}
return now.sum-2*(arr[r].y-arr[l].y);
}
void Merge(int l,int r,int ql,int qr){
if (ql>qr) return;
if (l==r){
for (int i=ql;i<=qr;i++){
ans=max(ans,Query(l,i));
}
return;
}
int mid=(ql+qr)>>1,best=-1e18,from=0;
for (int i=l;i<=r;i++){
if (mid-i+1>=m){
int c=Query(i,mid);
if (c>best){
best=c;
from=i;
}
}
}
ans=max(ans,best);
Merge(l,from,ql,mid-1);
Merge(from,r,mid+1,qr);
}
bool cmp(pii a,pii b){
if (a.y!=b.y) return a.y<b.y;
return a.x<b.x;
}
signed main(){
fast
cin>>n>>m;
for (int i=1;i<=n;i++){
cin>>arr[i].x>>arr[i].y;
uni.in(arr[i].x);
}
uni.build();
for (int i=1;i<=n;i++)
arr[i].x=uni.idx(arr[i].x);
sort(arr+1,arr+1+n,cmp);
for (int i=1;i<=n;i++){
root[i]=seg.add(1,n,root[i-1],arr[i].x,1);
}
Merge(1,n,m,n);
cout<<ans<<'\n';
}
