#include<iostream>

#include<cstdio>

#include<algorithm>

#define N 1000000

#define inf 0x7fffffff

#define LL long long

using namespace std;

LL n,val[N],d[N],f[N],s[N];

LL ans;

LL head[N],tot;

struct node{

    LL to,next;

}e[N];

void add(LL u,LL v){

    e[++tot].to=v,e[tot].next=head[u],head[u]=tot;

}

void dfs(LL u){

    for(LL i=head[u];i;i=e[i].next){

        LL v=e[i].to;

        if(v==f[u]) continue;

        dfs(v);

        val[u]=min(val[u],val[v]);

        s[u]+=s[v];

    }

    if(s[u]<d[u]) ans+=(d[u]-s[u])*val[u],s[u]=d[u];

}

int main()

{

    scanf("%lld",&n);

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

        scanf("%lld%lld%lld",&f[i],&d[i],&val[i]);

        add(i,f[i]),add(f[i],i);

    }

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

        if(f[i]==-){

            dfs(i);

            printf("%lld\n",ans);

            break;

        }

    }

    return ;

}