#include "tree.h"
#include <cstdio>
using namespace std;
typedef long long ll;
typedef vector<int> vi;
const int N=200003;
const int INF=0x3f3f3f3f;
int n,L,R;
vi vec[N];
int lc[N],rc[N],d[N];
int val[N],cap[N],tg[N];
inline void chmn(int &p,int v){if(p>v) p=v;}
void proc(int p,int v){
	if(!p) return;
	chmn(tg[p],v);
	chmn(val[p],v);
}
void pushdown(int p){
	if(tg[p]!=INF) proc(lc[p],tg[p]),proc(rc[p],tg[p]),tg[p]=INF;
}
int merge(int x,int y){
	if(!x||!y) return x|y;
	pushdown(x);pushdown(y);
	if(val[x]>val[y]) swap(x,y);
	rc[x]=merge(rc[x],y);
	if(d[rc[x]]>d[lc[x]]) swap(lc[x],rc[x]);
	d[x]=d[rc[x]]+1;
	return x;
}
vi w;ll res,sm[N];
int dfs(int u){
	if(vec[u].empty()){
		lc[u]=rc[u]=0;
		cap[u]=sm[u]=L;
		res+=(ll)L*w[u];
		val[u]=w[u];tg[u]=INF;
		return u;
	}
	else{
		int rt=0;
		sm[u]=0;
		for(int v:vec[u]) rt=merge(rt,dfs(v)),sm[u]+=sm[v];
		proc(rt,w[u]);
		while(sm[u]>R){
			pushdown(rt);
			if(cap[rt]>sm[u]-R){
				res+=(ll)(sm[u]-R)*val[rt];
				cap[rt]-=sm[u]-R;
				sm[u]=R;
			}
			else{
				res+=(ll)cap[rt]*val[rt];
				rt=merge(lc[rt],rc[rt]);
				sm[u]-=cap[rt];
			}
		}
		return rt;
	}
}
void init(vi P,vi W){
	n=P.size();w=W;
	for(int i=1;i<n;++i) vec[P[i]].emplace_back(i);
}
ll query(int _L,int _R){
	d[0]=-1;L=_L;R=_R;res=0;dfs(0);
	return res;
}