#include <bits/stdc++.h>
using namespace std;
#define int              long long int
#define double           long double
#define print(a)         for(auto x : a) cout << x << " "; cout << endl


const int M = 1000000007;
const int N = 3e5+9;
const int INF = 2e9+1;
const int LINF = 2000000000000000001;

inline int power(int a, int b, int mod=M) {
    int x = 1;
    a %= mod;
    while (b) {
        if (b & 1) x = (x * a) % mod; 
        a = (a * a) % mod;
        b >>= 1;
    }
    return x;
}


//_ ***************************** START Below *******************************

// 7 4
// 8 1 4 6 1 5 11


vector<int> a;

int consistency(int n, int k){

	sort(begin(a), end(a));
	
	vector<int> prefix(n+1);
	for(int i=0; i<n; i++ ){
		prefix[i+1] = prefix[i] + a[i];
	}
	
	vector<int> sufix(n+1);
	for(int i=n-1; i>=0; i--){
		sufix[i] = sufix[i+1] + a[i];
	}
	
	int ans = INF;
	
	for(int i=k-1; i<n; i++){
		int j = i-k+1;
		int m1 = j + (k-1)/2;
		int m2 = m1+1;
		
		if(k&1){
			int leftSum = prefix[m1+1]-prefix[j];
			int rightSum = sufix[m1+1] - sufix[i+1];
			
			ans = min(ans, a[m1] - leftSum + rightSum);
		}
		else{
			int leftSum = prefix[m1+1]-prefix[j];
			int rightSum = sufix[m1+1] - sufix[i+1];
			
			ans = min(ans,  -leftSum + rightSum);
			
			
			leftSum = prefix[m2+1] - prefix[j];
			rightSum = sufix[m2+1] - sufix[i+1];
			
			ans = min(ans, 2*a[m2] - leftSum + rightSum);
		}
		
	}
	
	return ans;
}















int practice(int n, int k){


    return 0;
}





void solve() {
    
    int n, k;
    cin>> n >> k;
    
    a.resize(n);
    for(int i=0; i<n; i++) cin >> a[i];
    
    cout << consistency(n, k) << endl;


}





int32_t main() {
    ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);

    int t = 1;
    // cin >> t;
    while (t--) {
        solve();
    }

    return 0;
}