//Bismillahirrahmanirrahim
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#include <bits/stdc++.h>
using namespace std;
typedef long long lo;
typedef pair< lo,lo > PII;
#define fi first
#define se second
#define int long long
#define mp make_pair
#define endl "\n"
#define pb push_back
#define fio() ios_base::sync_with_stdio(false);cin.tie(NULL);cout.tie(NULL)
#define FOR for(int i=1;i<=n;i++)
#define mid ((start+end)/2)
#define ort ((bas+son)/2)
const lo inf = 1000000000000000000;
const lo KOK = 100000;
const lo LOG = 30;
const lo li = 100005;
const lo mod = 1000000007;
int n,m,b[li],a[li],k,flag,t,dp[li][25],tree[li*4],cevap;
int cev;
string s;
PII p[li];
vector<int> v[li];
vector<PII> vec;
inline void dfs(int node,int ata){
for(int i=0;i<(int)v[node].size();i++){
int go=v[node][i];
if(go==ata)continue;
dfs(go,node);
}
if(p[node].fi!=0){
for(int i=p[node].fi;i<=p[node].fi;i++){
dp[node][i]=max(dp[node][i],(dp[node][p[node].fi]+p[node].se));
}
}
for(int i=1;i<=k;i++)dp[node][i]=max(dp[node][i],dp[node][i-1]);
//~ cout
for(int i=1;i<=k;i++){
dp[ata][i]+=(dp[node][i]);
}
}
inline void update(int node,int start,int end,int l,int r,int val){
if(start>end || start>r || end<l)return ;
if(start>=l && end<=r){tree[node]+=val;return ;}
update(node*2,start,mid,l,r,val),update(node*2+1,mid+1,end,l,r,val);
tree[node]=tree[node*2]+tree[node*2+1];
}
inline int query(int node,int start,int end,int l,int r){
if(start>end || start>r || end<l)return 0;
if(start>=l && end<=r)return tree[node];
return query(node*2,start,mid,l,r)+query(node*2+1,mid+1,end,l,r);
}
inline void solve(int node,int ata){
for(int i=0;i<(int)v[node].size();i++){
int go=v[node][i];
if(go==ata)continue;
solve(go,node);
}
if(p[node].fi!=0){
update(1,1,n,p[node].fi,p[node].fi,p[node].se);
cevap=max(cevap,query(1,1,n,1,p[node].fi));
}
}
inline void LIS(){
int len=1;
b[len]=a[1];
for(int i=2;i<=m;i++){
if(a[i]<b[1])b[1]=a[i];
else if(a[i]>=b[len])b[++len]=a[i];
else{
int bas=1;
int son=len;
while(bas<=son){
if(b[ort]>a[i])son=ort-1;
else bas=ort+1;
}
b[bas]=a[i];
}
}
printf("%lld\n",len);exit(0);
}
main(void){
scanf("%lld %lld %lld",&n,&m,&k);
int yes=0,yes1=0;
for(int i=2;i<=n;i++){
int x;
scanf("%lld",&x);
v[i].pb(x);
v[x].pb(i);
if(x==i-1)yes++;
}
for(int i=1;i<=m;i++){
int x,y,z;
scanf("%lld %lld %lld",&x,&y,&z);
if(z==1)yes1++;
cev+=z;
p[x].fi=y;
p[x].se=z;
vec.pb({x,y});
}
if(k<=20){
cev=0;
dfs(1,0);
for(int i=1;i<=k;i++)cev=max(cev,dp[i][k]);
}
if(yes==n-1 && yes1==m){
sort(vec.begin(),vec.end());
reverse(vec.begin(),vec.end());
for(int i=0;i<m;i++)a[i+1]=vec[i].se;
LIS();
}
printf("%lld\n",cev);
return 0;
}
