#include<cstdio>

using namespace std;

const int N=;

const int V=;

int n,m,rt,num_bian,num_ibian,num_huan,num_tarjan,num_que,

pw[N],pv[N],w[N],v[N],fm[N],to[N],head[N],nxt[N],ito[N],ihead[N],inxt[N],dfn[N],low[N],bel[N],que[N],in_que[N],dp[N][V],ru[N];

void add(int x,int y){

    to[++num_bian]=y,fm[num_bian]=x,nxt[num_bian]=head[x],head[x]=num_bian;

}

void iadd(int x,int y){

    ito[++num_ibian]=y,inxt[num_ibian]=ihead[x],ihead[x]=num_ibian,ru[y]++;

}

int min(int x,int y){return x>y?y:x;}

int max(int x,int y){return x>y?x:y;}

void tarjan(int x){

    dfn[x]=low[x]=++num_tarjan;

    que[++num_que]=x;in_que[x]=;

    for(int i=head[x],y;i;i=nxt[i])

        if(!dfn[y=to[i]])tarjan(y),low[x]=min(low[x],low[y]);

        else if(in_que[y])low[x]=min(low[x],dfn[y]);

    if(dfn[x]==low[x]){

        ++num_huan;

        int y;

        do{

            y=que[num_que--];

            in_que[y]=;

            bel[y]=num_huan;

        }while(y!=x);

    }

}

void dfs(int x){

    for(int i=ihead[x],y;i;i=inxt[i]){

        dfs(y=ito[i]);

        for(int j=m;j>=;--j)for(int k=j;k;--k)

            dp[x][j]=max(dp[x][j],dp[x][j-k]+dp[y][k]);

            //printf("dp[%d][%d]=%d\n",x,j,dp[x][j]);

    }

    if(v[x]!=)for(int i=m;i;--i)

        if(i>=v[x])dp[x][i]=dp[x][i-v[x]]+w[x];

        else dp[x][i]=;

}

void debug(){

    for(int i=;i<=n;++i)printf("%d ",bel[i]);puts("");

    for(int i=num_huan;i;--i)printf(":%d %d ",w[i],v[i]);puts("");

    printf("%d\n",rt);

}

int main(){

//freopen("text.in","r",stdin);

//freopen("1.out","w",stdout);

    scanf("%d%d",&n,&m);

    for(int i=;i<=n;++i)scanf("%d",&pv[i]);for(int i=;i<=n;++i)scanf("%d",&pw[i]);for(int i=,x;i<=n;++i){scanf("%d",&x);if(x)add(x,i);}

    for(int i=;i<=n;++i)if(!dfn[i])tarjan(i);

    for(int i=;i<=num_bian;++i)if(bel[fm[i]]!=bel[to[i]])iadd(bel[fm[i]],bel[to[i]]);

    for(int i=;i<=n;++i)w[bel[i]]+=pw[i],v[bel[i]]+=pv[i];

    for(int i=;i<=num_huan;++i)if(!ru[i])iadd(,i);

    dfs();

    printf("%d\n",dp[][m]);

    //debug();

    return ;

}

#include<bits/stdc++.h>

using namespace std;

int main(){

    for(int i=;i<=;++i){

        system("./1");

        system("./2");

        system("./rand");

        if(system("diff 1.out 2.out")){

            puts("Wrong Answer");return ;

        }

        else puts("Accepted");

    }

}

#include<bits/stdc++.h>

using namespace std;

const int N=;

int main(){

    freopen("text.in","w",stdout);

    srand((unsigned)time());

    int n=rand()%N+,m=rand()%N+;

    printf("%d %d\n",n,m);

    for(int i=;i<=n;++i){

        int v=rand()%n+;

        printf("%d ",v);

    }puts("");

    for(int i=;i<=n;++i){

        int w=rand()%n+;

        printf("%d ",w);

    }puts("");

    for(int i=,li;i<=n;++i){

        do

            li=rand()%n;

        while(li==i);

        printf("%d ",li);

    }puts("");

}