#include <bits/stdc++.h>
#define rep(i,j,k) for(int i=(j);i<=(k);i++)
#define per(i,j,k) for(int i=(j);i>=(k);i--)
#define uint unsigned int
#define ll long long
#define ull unsigned long long
#define db double
#define ldb long double
#define pii pair<int,int>
#define pll pair<ll,ll>
#define mkp make_pair
#define eb emplace_back
#define SZ(S) (int)S.size()
//#define mod 998244353
//#define mod 1000000007
#define inf 0x3f3f3f3f
#define linf 0x3f3f3f3f3f3f3f3f
using namespace std;

template <class T>
void chkmax(T &x,T y){
	if(x < y) x = y;
}

template <class T>
void chkmin(T &x,T y){
	if(x > y) x = y;
}

inline int popcnt(int x){
	return __builtin_popcount(x);
}

inline int ctz(int x){
	return __builtin_ctz(x);
}


/*ll power(ll p,int k = mod - 2){
	ll ans = 1;
	while(k){
		if(k % 2 == 1) ans = ans * p % mod;
		p = p * p % mod;
		k /= 2;	
	}
	return ans;
}*/
int n,K;
int a[205],b[205],c[205];

ll ans[205][205],val[205][205];
int main(){
//	freopen("test.in","r",stdin);
//	freopen("test.ans","w",stdout);
	scanf("%d%d",&n,&K);
	rep(i,1,n) scanf("%d",&a[i]);
	rep(i,1,n) scanf("%d",&b[i]);

	ll answer = -linf;
	rep(l,1,n){	
		rep(r,l,n){
			int m = r - l + 1;
			ans[l][r] = -linf;
			if(m < K) continue;
			rep(i,1,m) c[i] = b[i + l - 1];
			sort(c + 1,c + m + 1);
			ans[l][r] = 0;
			rep(k,l,r) ans[l][r] -= a[k];
			rep(i,1,K) ans[l][r] += c[m - i + 1];
			chkmax(answer,ans[l][r]);
		}	
	}
	rep(r,1,n){
		int pl = inf,pr = 0;
		rep(l,1,r){
			if(ans[l][r] == answer){
				chkmin(pl,l);
				chkmax(pr,l);
				cerr << l << " " << r << "\n";
			}
		}
		rep(l,pl,pr) assert(ans[l][r] == answer);
	}
	cerr << "fin\n";
	printf("%lld\n",answer);
	return 0;
}