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#include <fstream>
#include <vector>
using namespace std;
ifstream cin("lca.in");
ofstream cout("lca.out");
#define maxim 100005
vector<int> graf[maxim];
int d[maxim],tata[maxim];
int n,m,i,j,x,a,b;
void dfs(int nod, int nivel)
{
d[nod]=nivel;
for(int i=0; i<graf[nod].size(); i++)
{
if(!tata[graf[nod][i]])
{
tata[graf[nod][i]]=nod;
dfs(graf[nod][i],nivel+1);
}
}
}
int lca(int a, int b)
{
while(a!=b)
{
if(d[a]>d[b])
a=tata[a];
else
b=tata[b];
}
return a;
}
int main()
{
cin>>n>>m;
for(i=2; i<=n; i++)
{
cin>>x;
graf[x].push_back(i);
}
dfs(1,1);
for(i=1; i<=m; i++)
{
cin>>a>>b;
cout<<lca(a,b)<<"\n";
}
}