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#include <bits/stdc++.h>
using namespace std;
int n,m,a,poz[1000],x,y,l,k,pozy,pozx,lg[1000],rmq[1000][17];
bool viz[1000];
vector<int>v[1000],eu;
void euler(int x)
{
if(!viz[x])
{
viz[x]=1;
poz[x]=eu.size()+1;
}
eu.push_back(x);
for(int i=0;i<v[x].size();i++)
{
euler(v[x][i]);
eu.push_back(x);
}
return;
}
int main()
{
ifstream cin("lca.in");
ofstream cout("lca.out");
cin>>n>>m;
lg[1]=0;
for(int i=2;i<=n;i++)
{
cin>>a;
v[a].push_back(i);
lg[i]=lg[i/2]+1;
}
euler(1);
for(int i=0;i<eu.size();i++)
{
//cout<<eu[i]<<' ';
rmq[0][i+1]=eu[i];
}
//cout<<'\n';
n=eu.size();
for(int i=1;(1<<i)<=n;i++)
{
for(int j=1;j<=n-(1<<i)+1;j++)
{
rmq[i][j]=min(rmq[i-1][j],rmq[i-1][j+(1<<(i-1))]);
//cout<<rmq[i][j]<<' ';
}
//cout<<'\n';
}
/* for(int i=0;(1<<i)<=n;i++)
{
cout<<'\n';
for(int j=1;j<=n;j++)
cout<<rmq[i][j]<<' ';
}
cout<<'\n';*/
// for(int i=1;i<=n;i++)
//lg[i]=lg[i/2]+1;
for(;m;m--)
{
cin>>x>>y;
pozx=min(poz[x],poz[y]);
pozy=max(poz[x],poz[y]);
l=pozy-pozx+1;
k=lg[l];
//cout<<k<<' '<<pozx<<' '<<pozy<<'\n';
cout<<min(rmq[k][pozx],rmq[k][pozy-(1<<(k))+1])<<'\n';
}
return 0;
}