#include <fstream>
#include <vector>
using namespace std;
ifstream f ("lca.in");
ofstream g ("lca.out");
const int nmax=2e5+3;
vector <int> v[nmax];
int usu[nmax],k,f1[nmax],lvl[nmax],lg[nmax],r[40][nmax],a,b,dif,l,sol,ad,n,m;
void dfs(int nod,int lv)
{
      usu[++k]=nod;
      f1[nod]=k;
      lvl[k]=lv;
      for(int i=0;i<v[nod].size();++i)
      {
            dfs(v[nod][i],lv+1);
            usu[++k]=nod;
            lvl[k]=lv;
      }
}
void rmq()
{
      for(int i=2;i<=k;++i) lg[i]=lg[i/2]+1;
      for(int i=1;i<=k;++i) r[0][i]=i;
      for(int i=1;(1<<i)<k;++i)
      {
            for(int j=1;j+(1<<i)<=k;++j)
            {
                  int l=1<<(i-1);
                  r[i][j]=r[i-1][j];
                  if(lvl[r[i-1][j+l]]<lvl[r[i][j]]) r[i][j]=r[i-1][j+l];
            }
      }
}
int lca(int x,int y)
{
      a=f1[x];
      b=f1[y];
      if(a>b) swap(a,b);
      dif=b-a+1;
      l=lg[dif];
      sol=r[l][a];
      ad=dif-(1<<l);
      if(lvl[sol]>lvl[r[l][a+ad]]) sol=r[l][a+ad];
      return usu[sol];
}
int main()
{
      f>>n>>m;
      for(int i=2;i<=n;++i)
      {
            f>>a;
            v[a].push_back(i);
      }
      dfs(1,0);
      rmq();
      while(m--)
      {
            f>>a>>b;
            g<<lca(a,b)<<'\n';
      }
      return 0;
}