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#include <fstream>
#include <vector>
using namespace std;
ifstream cin("lca.in");
ofstream cout("lca.out");
int mar[100001];
int par[100001];
int heavy[100001];
int tp[100001];
int nr[100001];
int adan[100001];
int cnt;
vector<int> v[100001];
void dfs(int tata,int nod){
mar[nod]=1;
for(auto it:v[nod]){
if(it==tata) continue;
adan[it]=adan[nod]+1;
par[it]=nod;
dfs(nod,it);
mar[nod]+=mar[it];
if(mar[it]>mar[heavy[nod]]) heavy[nod]=it;
}
}
void dfs1(int tata,int nod,int top){
nr[nod]=cnt;cnt++;
tp[nod]=top;
if(!heavy[nod]) return;
dfs1(nod,heavy[nod],top);
for(auto it:v[nod]){
if(it==tata || it==heavy[nod]) continue;
dfs1(nod,it,it);
}
}
int lca(int a,int b){
if(a>b) swap(a,b);
while(tp[a]!=tp[b]){
if(adan[a]<=adan[b]) b=par[tp[b]];
else a=par[tp[a]];
}
printf("\n");
if(adan[a]<adan[b]) return a;
return b;
}
int main()
{
int n,m,i,a,b;
cin>>n>>m;
for(i=2;i<=n;i++){
cin>>a;
v[a].push_back(i);
}
par[1]=1;
dfs(1,1);
dfs1(1,1,1);
for(i=1;i<=n;i++){
printf("%d ",adan[i]);
}printf("\n");
for(i=1;i<=m;i++){
cin>>a>>b;
cout<<lca(a,b)<<"\n";
}
return 0;
}