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#include <fstream>
#include <cstring>
#include <vector>
using namespace std;
ifstream fin("lca.in");
ofstream fout("lca.out");
int i,n,m,nod,poz,j,t[18][100001],lv[100001],aux,a,b;
vector<int> v[100001];
int lca(int a,int b)
{
int i;
if(lv[a]<lv[b])swap(a,b);
aux=lv[a]-lv[b];
for(i=0;(1<<i)<=aux;i++)if((aux&(1<<i))==1)a=t[i][a];
for(i=0;(1<<i)<lv[b];i++);
if(a==b)return a;
for(i--;i>=0;i--)
if(t[i][a]&&t[i][a]!=t[i][b]) a=t[i][a],b=t[i][b];
return t[0][a];
}
void dfs(int nod, int lvl)
{
lv[nod]=lvl;
for(int i=0;i<v[nod].size();i++)
dfs(v[nod][i],lvl+1);
}
int main(){
fin>>n>>m;
for(i=2;i<=n;i++){fin>>t[0][i];v[t[0][i]].push_back(i);}
for(i=1,aux=2;aux<=n;i++,aux<<=1)for(j=1;j<=n;j++)t[i][j]=t[i-1][t[i-1][j]];
dfs(1,1);
for(i=1;i<=m;i++){fin>>a>>b;fout<<lca(a,b)<<"\n";}
return 0;
}