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#include <bits/stdc++.h>
#define all(vec) vec.begin(),vec.end()
#define pb push_back
#define EB emplace_back
#define EM emplace
#define FI first
#define SE second
#define SZ(a) ((int) a.size())
#define FOR(i, a, b) for (long long i = (a); i <= (b); ++i)
#define ROF(i, a, b) for (long long i = (a); i >= (b); --i)
#define debug(var) cerr << #var <<":"<<var<<"\n";
#define lson(var) (var<<1)
#define rson(var) ((var<<1)+1)
using namespace std;
using ll = long long;using ull = unsigned long long;
using DB=double;using LD=long double;
using pdd = pair<DB,DB>;using plb = pair<ll,bool>;
using pll = pair<ll,ll>;using vll=vector<ll>;using vb=vector<bool>;
using tll = tuple<ll,ll,ll>;
using vpll = vector<pll>;
using arr3 = array<ll,3> ;using arr2 = array<ll,2>;
constexpr ll MAXN=(ll)1e6+10,INF=(ll)1e17+9;
constexpr ll mod=(ll)1e9+7;
constexpr double eps=1e-8;const double pi=acos(-1.0);
ll N,M,Q,X,K,T,lT,A[MAXN],F[MAXN];
struct STtree{
#define FOR(i, a, b) for (long long i = (a); i <= (b); ++i)
#define ROF(i, a, b) for (long long i = (a); i >= (b); --i)
using ll=long long;
ll n;
vector<vector<ll> > fa,g;
vector<ll> dep;vector<bool> OK;
STtree(ll n){
this->n=n;
fa.resize(n+5,vector<ll>(35,0));
dep.resize(n+5,0);
OK.resize(n+5,0);
g.resize(n+5);
}
void dfs(ll u,ll p){
fa[u][0]=p;
dep[u]=dep[p]+1;
for(auto &v:g[u]){
if(v==p) continue;
dfs(v,u);
}
}
ll findk(ll u,ll k){
if(k==0) return u;
ROF(i,30,0){
if(k>>i&1){
u=fa[u][i];
}
}
return u;
}
ll findlow(ll u){
if(OK[u]) return u;
ROF(i,30,0){
if(fa[u][i] && !OK[fa[u][i]]){
u=fa[u][i];
}
}
return fa[u][0];
}
void add(ll u,ll v){
g[u].push_back(v);
g[v].push_back(u);
}
void work(ll root=1){
OK[0]=true;OK[1]=true;
dfs(root,0);
FOR(u,1,n){
FOR(i,1,__lg(dep[u])){
fa[u][i]=fa[fa[u][i-1]][i-1];
}
}
}
};
inline void __();
int main()
{
ios::sync_with_stdio(false);
cin.tie(0);cout.tie(0);
__();
return 0;
}
inline void __(){
cin>>N>>K;
STtree tr(N);
FOR(i,2,N){
cin>>F[i];
tr.add(F[i],i);
}
tr.work();
FOR(i,1,K){
ll u,l,r;
cin>>u>>l>>r;
ll low=tr.findlow(u);
if(low==u){
cout<<l<<"\n";
return;
}
ll dis=tr.dep[u]-tr.dep[low],time=r-l+1;
ll cnt=0;
ll mn=min(time,dis);
ll v=tr.findk(u,dis-mn);
if(v==u){
ll ans=dis+l-1;
cout<<ans<<"\n";
return;
}
while(v!=low){
tr.OK[v]=true;
v=tr.fa[v][0];
}
}
cout<<-1<<"\n";
}
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