#include <bits/stdc++.h>
using namespace std ;

const int NMAX = 100001 ;

vector < int > v [ NMAX ] ;
ifstream f ("lca.in") ;
ofstream g ("lca.out") ;

    void dfs ( int nod , int Father [ NMAX ] , int Level [ NMAX ] , int GR [ NMAX ] , int sqrtn )
    {
    Level [ nod ] = Level [ Father [ nod ] ] + 1 ;  // adancimea nodului
    // dfs va fi apelat in main din nodul 1
    if ( Level [ nod ] < sqrtn )   // elementele din prima grupa
        GR [ nod ] = 1 ;
    else
    {
        if ( ! ( Level [ nod ] % sqrtn ) )
            GR [ nod ] = Father [ nod ] ;
        else
            GR [ nod ] = GR [ Father [ nod ] ] ;
    }
    for( size_t i = 0 ; i < v [ nod ].size() ; ++ i )
        dfs ( v [ nod ][ i ] , Father , Level , GR , sqrtn ) ;
    }

    int LCA ( int x , int y , int Father [ NMAX ] , int Level [ NMAX ] , int GR [ NMAX ] )
    {

    while ( GR [ x ] != GR [ y ] )  // cat timp nu sunt int aceeasi grupa
    {                               // avansam nodul inferior cu cate sqrt ( N ) pozitii ( o grupa )
        if ( Level [ x ] > Level [ y ] )
            x = GR [ x ] ;
        else
            y = GR [ y ] ;
    }

    while ( x != y )                // cand sunt in aceeasi grupa
    {                               // urcam " din tata in tata "
        if ( Level [ x ] > Level [ y ] )
            x = Father [ x ] ;
        else
            y = Father [ y ] ;
    }
    return x ;

    }



int main ()
{
    int Father [ NMAX ]= {0} ,  Level [ NMAX ] = {0} ,  GR [ NMAX ] ={0} ;
    int n , q , i ; f >> n >> q ;
    for ( i = 2 ; i <= n ; ++ i )
        {

            f >> Father [ i ] ;
            v [ Father [ i ] ].push_back( i ) ;
        }
    dfs ( 1 , Father , Level , GR , sqrt ( n ) ) ;
    //for ( i = 1 ; i <= n ; ++ i )   g << Father [ i ] << " " ;
    //for ( i = 1 ; i <= n ; ++ i )   g << GR [ i ] << " " ;
    //g << "\n" ;
    //for ( i = 1 ; i <= n ; ++ i )   g << Level [ i ] << " " ;
    while ( q -- )
    {
        int a , b ; f >> a >> b ;
        g<< LCA ( a , b , Father , Level ,GR ) << "\n" ;
    }
}