#include <iostream>
#include <fstream>
#include <vector>
using namespace std;
ifstream f("lca.in");
ofstream g("lca.out");

vector <int> v[100005];
int n,e[200005],k,use[100005],ind[100005],niv[100005],lg[200005],rmq[200005][19];

void BF(int x,int ad)
{ int i;
   use[x]=1;
   k++; e[k]=x; ind[x]=k;
   niv[x]=ad;

   for(i=0;i<v[x].size();i++)
   if (!use[v[x][i]])
    { BF(v[x][i],ad+1);
      k++; e[k]=x;
    }
}

void Build()
{ int i,len;
   for(i=2;i<=k;i++)
    lg[i]=lg[i/2]+1;

  for(i=1;i<=k;i++)
   {rmq[i][0]=e[i];

   }
  for(len=1;len<=lg[k];len++)
   for(i=1;i<=k-(1<<len)+1;i++)
    if (niv[rmq[i][len-1]]<niv[rmq[i+(1<<(len-1))][len-1]])
       rmq[i][len]=rmq[i][len-1];
        else rmq[i][len]=rmq[i+(1<<(len-1))][len-1];


}

int Solve(int x,int y)
{ if (ind[x]>ind[y]) swap(x,y);
   int len=ind[y]-ind[x]+1,p=lg[len];

  if (niv[rmq[ind[x]][p]]<niv[rmq[ind[y]-(1<<p)+1][p]])
    return rmq[ind[x]][p];
   else return rmq[ind[y]-(1<<p)+1][p];
}

int main()
{ int i,q,x,y;
   f>>n>>q;
   for(i=2;i<=n;i++)
   { f>>x;
      v[i].push_back(x);
      v[x].push_back(i);
   }

   BF(1,1);
   Build();
   for(i=1;i<=q;i++)
   { f>>x>>y;
      g<<Solve(x,y)<<"\n";
   }
    return 0;
}