#pragma GCC target("avx2")
#pragma GCC optimize("O3")
#pragma GCC optimize("unroll-loops")

#include<bits/stdc++.h>
using namespace std;

typedef long long ll;

#define rep(i, s, n) for (int i = (int)(s); i < (int)(n); i++)
#define rrep(i, s, n) for (int i = (int)(n)-1; i >= (int)(s); i--)

template <typename T> bool chmin(T &a, const T &b) {
	if (a <= b) return false;
	a = b;
	return true;
}

template <typename T> bool chmax(T &a, const T &b) {
	if (a >= b) return false;
	a = b;
	return true;
}

template <typename T> T max(vector<T> &a){
	assert(!a.empty());
	T ret = a[0];
	for (int i=0; i<(int)a.size(); i++) chmax(ret, a[i]);
	return ret;
}

template <typename T> T min(vector<T> &a){
	assert(!a.empty());
	T ret = a[0];
	for (int i=0; i<(int)a.size(); i++) chmin(ret, a[i]);
	return ret;
}

template <typename T> T sum(vector<T> &a){
	T ret = 0;
	for (int i=0; i<(int)a.size(); i++) ret += a[i];
	return ret;
}

bool dp[52][700][700];

int main(){
	ios_base::sync_with_stdio(false);
	cin.tie(NULL);

	int n, f; cin >> n >> f;
	vector<ll> a(2*n);
	vector<int> c(2*n);
	rep(i,0,n){
		cin >> a[i];
		a[i+n] = a[i];
	}
	rep(i,0,n){
		cin >> c[i];
		c[i]--;
		c[i+n] = c[i];
	}

	rep(i,0,50){
		rep(j,0,2*n){
			rep(k,0,2*n+1){
				dp[i][j][k] = false;
			}
		}
	}

	rep(i,0,2*n){
		dp[c[i]][i][i+1] = true;
	}

	rep(len,2,n+1){
		rep(i,0,2*n+1-len){
			if (i >= n){
				rep(k,0,50){
					dp[k][i][i+len] = dp[k][i-n][i-n+len];
				}
				continue;
			}
			rep(k,0,50){				
				rep(j,i+1,i+len){
					if (dp[k][i][i+len]) break;
					if (!dp[k][i][j]) continue;
					rep(l,max(0,k-f),min(50,k+f+1)){
						if (dp[l][j][i+len]){
							dp[k][i][i+len] = true;
							break;
						}
					}
				}
				rep(j,i+1,i+len){
					if (dp[k][i][i+len]) break;
					if (!dp[k][j][i+len]) continue;
					rep(l,max(0,k-f),min(50,k+f+1)){
						if (dp[l][i][j]){
							dp[k][i][i+len] = true;
							break;
						}
					}
				}
				
			}
		}
	}

	vector<ll> rui(2*n+1);
	rep(i,0,2*n){
		rui[i+1] += rui[i] + a[i];
	}

	ll ans = -1e18;
	rep(i,0,50){
		rep(j,0,2*n){
			rep(k,0,2*n+1){
				if (dp[i][j][k]){
					chmax(ans, rui[k] - rui[j]);
				}
			}
		}
	}

	cout << ans << '\n';

}