[十二省联考]春节十二响

//Love and Freedom.
#include<cstdio>
#include<cmath>
#include<algorithm>
#include<cstring>
#include<queue>
#define ll long long
#define inf 20021225
#define N 200100
using namespace std;

struct edge{int to,lt;}e[N];
int in[N],cnt; int id[N],n; ll st[N],val[N]; priority_queue<ll> q[N];
void add(int x,int y)
{
    e[++cnt].to=y; e[cnt].lt=in[x]; in[x]=cnt;
}
void dfs(int x)
{
    id[x]=x;
    for(int i=in[x];i;i=e[i].lt)
    {
        int y=e[i].to; dfs(y);
        if(i==in[x])
            id[x]=id[y];
        else
        {
            if(q[id[x]].size()<q[id[y]].size())    swap(id[x],id[y]);
            int tot=0;
            while(!q[id[y]].empty())
                st[++tot]=max(q[id[y]].top(),q[id[x]].top()),q[id[y]].pop(),q[id[x]].pop();
            for(int i=1;i<=tot;i++)    q[id[x]].push(st[i]);
        }
    }
    q[id[x]].push(val[x]);
}
int main()
{
    scanf("%d",&n); int fa;
    for(int i=1;i<=n;i++)
        scanf("%lld",&val[i]);
    for(int i=2;i<=n;i++)
        scanf("%d",&fa),add(fa,i);
    dfs(1); ll ans=0;
    while(!q[id[1]].empty())    ans+=q[id[1]].top(),q[id[1]].pop();
    printf("%lld\n",ans);
    return 0;
}