#include<bits/stdc++.h>
#define int long long
using namespace std;
#define fi first
#define sc second
#define pii pair<int,int>
#define pdd pair<double,double>
#define pb push_back
#define umap unordered_map
#define mset multiset
#define pq priority_queue
#define ull unsigned long long
#define i128 __int128
#define ld long double
#define fixs fixed<<setprecision
#define FileIn(x) freopen(x".in","r",stdin)
#define FileOut(x) freopen(x".out","w",stdout)
#define FileIO(x) FileIn(x),FileOut(x);
const int maxn=1e5+10;
int lb(int x){
    return x&(-x);
}
struct BIT{
    int c[maxn],N;
    void init(int n){
        N=n;
        for(int i=1;i<=n;i++) c[i]=0;
    }
    void upd(int x,int k){
        for(;x<=N;x+=lb(x)) c[x]+=k;
    }
    int query(int x){
        int sum=0;
        for(;x;x-=lb(x)) sum+=c[x];
        return sum;
    }
}tr,trs;
int n,res,a[maxn],k,w[maxn],num[maxn],cnt,t[maxn];
void solve(){
    cin>>n>>k,tr.init(n),trs.init(n),res=1e18;
    for(int i=1;i<=n;i++) cin>>a[i],num[i]=a[i];
    sort(num+1,num+n+1),cnt=unique(num+1,num+n+1)-num-1;
    for(int i=1;i<=n;i++) w[i]=lower_bound(num+1,num+cnt+1,a[i])-num,t[w[i]]=a[i];
    for(int i=1;i<k;i++) tr.upd(w[i],1),trs.upd(w[i],a[i]);
    for(int i=k;i<=n;i++){
        tr.upd(w[i],1),trs.upd(w[i],a[i]);
        int l=1,r=n,p=0,mid=0;
        while(l<=r) mid=(l+r)>>1,(tr.query(mid)>=k/2+(k&1)?p=mid,r=mid-1:l=mid+1);
        int x=t[p]*tr.query(p)-trs.query(p),y=(trs.query(n)-trs.query(p))-t[p]*(tr.query(n)-tr.query(p));
        res=min(res,x+y),tr.upd(w[i-k+1],-1),trs.upd(w[i-k+1],-a[i-k+1]);
    }
    cout<<res<<endl;
}
signed main(){
    ios::sync_with_stdio(false);
    cin.tie(0),cout.tie(0);
    int t=1;
    // cin>>t;
    while(t--) solve();
    return 0;
}
/*
Samples
input:

output:

THINGS TODO:
检查freopen，尤其是后缀名
检查空间
检查调试语句是否全部注释
*/