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#include<bits/stdc++.h>
using namespace std;
const int NMAX=10005;
vector<int>v[NMAX];
int p[NMAX],d[NMAX];
void dfs(int nod)
{
for(auto it:v[nod])
{
if(!d[it])
{
d[it]=d[nod]+1;
dfs(it);
}
}
}
int lca(int a,int b)
{
if(a==b)return a;
if(d[a]>d[b])swap(a,b);
if(d[a]<d[b])return lca(a,p[b]);
if(d[a]==d[b])return lca(p[a],p[b]);
}
int main()
{
freopen("lca.in","r",stdin);
freopen("lca.out","w",stdout);
int m,n,k,a,b,i;
cin>>n>>m;
for(i=2;i<=n;i++)
{
cin>>p[i];
v[i].push_back(p[i]);
v[p[i]].push_back(i);
}
d[1]=1;
dfs(1);
for(i=1;i<=m;i++)
{
cin>>a>>b;
cout<<lca(a,b)<<'\n';
}
}