#include<bits/stdc++.h>
#define int long long
using namespace std;
const int N=1e5+10;
int a[N],b[N],n,k;
int dp[N][21][21];
bool cmp(int x,int y){
	return x>y;
}
int dfs(int round,int s_a,int s_b){
	if(round==2*n) return 0;
	if(dp[round][s_a][s_b]!=-1) return dp[round][s_a][s_b];
	int nowa=round/2-s_b+s_a;
	int nowb=(round+1)/2-s_a+s_b;
	int ans=-1e18;
	if(round%2==0){
		if(s_a<k&&nowa<n) ans=max(ans,dfs(round+1,s_a+1,s_b)+a[nowa+1]);
		ans=max(ans,dfs(round+1,s_a,s_b));
		return dp[round][s_a][s_b]=ans;
	}
	else{
		ans=1e18;
		if(s_b<k&&nowb<n) ans=min(ans,dfs(round+1,s_a,s_b+1)-b[nowb+1]);
		ans=min(ans,dfs(round+1,s_a,s_b));
		return dp[round][s_a][s_b]=ans;
	}
}
void solve()
{
   memset(dp,-1,sizeof(dp));
   cin>>n>>k;
   for(int i=1;i<=n;i++) cin>>a[i];
   for(int i=1;i<=n;i++) cin>>b[i];
   sort(a+1,a+1+n,cmp);
//   for(int i=1;i<=n;i++) cout<<a[i]<<' ';
//   cout<<'\n';
   sort(b+1,b+1+n,cmp);
   dfs(0,0,0);
   cout<<dp[0][0][0]<<'\n';
}
signed main()
{
	ios::sync_with_stdio(false);
	cin.tie(0),cout.tie(0);
	int t=1;
//	cin>>t;
	while(t--) solve();
	return 0;
}