#include<bits/stdc++.h>
using namespace std;
#define rep(i,n) for(ll i=0;i<n;i++)
#define repl(i,l,r) for(ll i=(l);i<(r);i++)
#define per(i,n) for(ll i=(n)-1;i>=0;i--)
#define perl(i,r,l) for(ll i=r-1;i>=l;i--)
#define fi first
#define se second
#define pb push_back
#define ins insert
#define pqueue(x) priority_queue<x,vector<x>,greater<x>>
#define all(x) (x).begin(),(x).end()
#define CST(x) cout<<fixed<<setprecision(x)
#define rev(x) reverse(x);
using ll=long long;
using vl=vector<ll>;
using vvl=vector<vector<ll>>;
using pl=pair<ll,ll>;
using vpl=vector<pl>;
using vvpl=vector<vpl>;
const ll MOD=1000000007;
const ll MOD9=998244353;
const int inf=1e9+10;
const ll INF=4e18;
const ll dy[8]={-1,0,1,0,1,1,-1,-1};
const ll dx[8]={0,-1,0,1,1,-1,1,-1};
template<class T> inline bool chmin(T& a, T b) {
    if (a > b) {
        a = b;
        return true;
    }
    return false;
}
template<class T> inline bool chmax(T& a, T b) {
    if (a < b) {
        a = b;
        return true;
    }
    return false;
}
ll n,k;
vl v(200010);
ll check1(ll d){
    ll sum=0;
    rep(i,n){
        if(i<k)sum+=abs(d-v[i]);
        else sum-=abs(d-v[i]);
    }
    return sum;
}
ll check2(ll d){
    ll sum=0;
    rep(i,n){
        if(k>=n-i)sum+=abs(d-v[i]);
        else sum-=abs(d-v[i]);
    }
    return sum;
}
int main(){
    cin >> n >>k;
    rep(i,n)cin >> v[i];
    ll ok=v[0],ng=v[n-1];
    rep(hoge,200){
        ll d=ok*2+ng,e=ng*2+ok;
        d/=3;e/=3;
        if(check1(d)>check1(e))ok=d;
        else ng=e;
        //cout << sum <<endl;
    }
    ll ans=INF;
    for(int x=max(ok-100,v[0]);x<=min(ok+100,v[n-1]);x++){
        chmin(ans,check1(x));
    }
    ok=v[0],ng=v[n-1];
    rep(hoge,200){
        ll d=ok*2+ng,e=ng*2+ok;
        d/=3;e/=3;
        if(check2(d)>check2(e))ok=d;
        else ng=e;
        //cout << sum <<endl;
    }
    for(int x=max(ok-100,v[0]);x<=min(ok+100,v[n-1]);x++){
        chmin(ans,check2(x));
    }
    cout << ans <<endl;
}