#include <iostream>
#include <fstream>

using namespace std;

ifstream fin ("lca.in");
ofstream fout ("lca.out");

struct nod
{
    int info;
    nod * urm;
}*vecin[100001];
nod * prim[100001];

const int INFINIT=100000;
int e[200001], tt[100001], poz[100001], lev[100001];
int mn[19][200001], pozmin[19][200001];
int lg, log;

void reprez(int x)
{
    e[++lg]=x;
    poz[x]=lg;

    nod * t = prim[x];
    while(t!=NULL)
    {
        lev[t->info] = lev[x]+1;
        reprez(t->info);
        e[++lg]=x;
        t=t->urm;
    }
}

int lca (int x, int y)
{
    int rez, salv, i;
    if(y<x) swap(x, y);

    rez=INFINIT;

    for(i=log; i>=0; i--)
    {
        if( (y-x) & (1<<i) )
        {
            rez=min(rez, mn[i][x]);
            if(rez==mn[i][x]) salv=pozmin[i][x];
            x+=(1<<i);
        }
    }

    return e[salv];

}

int main()
{
    //mai intai construiesc vectorul e[] ce reprezinta reprezentarea euler
    int n, k, i, j;

    fin>>n>>k;
    for(i=2; i<=n; i++)
    {
        fin>>tt[i];
        //il adaug pe i la fiii lui tt[i];

        nod * aux = new nod;
        aux->info=i;
        aux->urm=NULL;
        if(prim[ tt[i] ]==NULL)
        {
            prim[ tt[i] ]=aux;
            vecin[ tt[i] ]=aux;
        }
        else
        {
            vecin[ tt[i] ]->urm=aux;
            vecin[ tt[i] ]=aux;
        }
    }

    reprez(1);

    for(i=1; i<=lg; i++)
    {
        mn[0][i]=min(lev[ e[i] ], lev[ e[i+1] ]);
        if(mn[0][i]==lev[ e[i+1] ])pozmin[0][i]=i+1;
        else pozmin[0][i]=i;
    }

    for(log=1; (1<<log)<lg; log++);

    for(i=1; i<=log; i++)
    {
        for(j=1; j<=lg; j++)
        {
            mn[i][j] = min(mn[i-1][j], mn[i-1][j+(1<<(i-1))]);
            if(mn[i][j]==mn[i-1][j]) pozmin[i][j]=pozmin[i-1][j];
            else pozmin[i][j]=pozmin[i-1][j+(1<<(i-1))];
        }
    }

    int x, y;
    for(i=1; i<=k; i++)
    {
        fin>>x>>y;
        fout<<lca(poz[x], poz[y])<<"\n";
    }



}