#include <bits/stdc++.h>

using namespace std;
typedef long long ll;
typedef pair<ll, ll> p_ll;

template<class T>
void debug(T itr1, T itr2) { auto now = itr1; while(now<itr2) { cout << *now << " "; now++; } cout << endl; }
#define repr(i,from,to) for (ll i=(ll)from; i<(ll)to; i++)
#define all(vec) vec.begin(), vec.end()
#define rep(i,N) repr(i,0,N)
#define per(i,N) for (int i=(int)N-1; i>=0; i--)

const ll MOD = pow(10,9)+7;
const ll LLINF = pow(2,61)-1;
const int INF = pow(2,30)-1;

vector<ll> fac;
void c_fac(int x=pow(10,6)+10) { fac.resize(x,true); rep(i,x) fac[i] = i ? (fac[i-1]*i)%MOD : 1; }
ll inv(ll a, ll m=MOD) { ll b = m, x = 1, y = 0; while (b!=0) { int d = a/b; a -= b*d; swap(a,b); x -= y*d; swap(x,y); } return (x+m)%m; }
ll nck(ll n, ll k) { return fac[n]*inv(fac[k]*fac[n-k]%MOD)%MOD; }
ll gcd(ll a, ll b) { if (a<b) swap(a,b); return b==0 ? a : gcd(b, a%b); }
ll lcm(ll a, ll b) { return a/gcd(a,b)*b; }


int main() {
  ll N, C; cin >> N >> C;
  ll L[N]; rep(i,N) cin >> L[i];
  ll W[N]; rep(i,N) cin >> W[i];

  ll dp[C+1][51][51][4] = {}; 
  rep(c,C+1) rep(now,51) rep(prev,51) repr(cnt,1,4) dp[c][now][prev][cnt] = -1*LLINF;
  per(c,C+1) rep(now,51) rep(prev,51) rep(count,4) {
    if (c==0||now==prev) continue;
    rep(i,N) {
      if (L[i]==now||L[i]==prev) continue;
      if ((now>prev&&now>L[i])||(now<prev&&now<L[i])&&c>=W[i]) {
        ll nc = min(3ll,count+1);
        dp[c-W[i]][L[i]][now][nc] = max(dp[c-W[i]][L[i]][now][nc], dp[c][now][prev][count]+L[i]);
      }
    }
    if (c!=C) dp[c][now][prev][count] = max(dp[c][now][prev][count], dp[c+1][now][prev][count]);
  }

  ll result = 0; rep(now,51) rep(prev,51) result = max(result, dp[0][now][prev][3]);
  cout << result << endl;

  return 0;
}