#include <iostream>
#include <fstream>
#include <vector>

using namespace std;

ifstream f("lca.in");
ofstream g("lca.out");

vector < vector<int>> v, lant;

int tati[100010], nivel[100010], boss[100010], k = 1, care[100010], dp[30][200010], lg[100010];
int nivel_lant[100010];

int DFS(int nod, int nivel_actual)
{
    nivel[nod] = nivel_actual;
    int ok = 0;
    for(int i = 0 ; i < v[nod].size(); i++)
    {
        ok = 1;
        DFS(v[nod][i], nivel_actual + 1);
    }
    if(ok == 0)
    {
        lant[k].push_back(nod);
        care[nod] = k;
        k++;
    }
    else
    {
        int pe_care, maxim = 0;
        for(int i = 0; i < v[nod].size(); i++)
        {
            if(lant[care[v[nod][i]]].size() > maxim)
            {
                maxim = lant[care[v[nod][i]]].size();
                pe_care = care[v[nod][i]];
            }
        }
        lant[pe_care].push_back(nod);
        care[nod] = pe_care;
        for(int i = 0; i < v[nod].size(); i++)
        {
            if(care[v[nod][i]] != pe_care)
                boss[care[v[nod][i]]] = nod;
        }

    }
    return 0;
}

int creez_dinamica(int k)
{
    for(int j = 1 ; j < 15; j++)
        for(int i = 1; i <= k; i++)
            dp[j][i] = dp[j - 1][dp[j - 1][i]];
}

int query(int x, int y)
{
    /*if(care[x] == care[y])
    {
        if(nivel[x] > nivel[y])
            return y;
        else
            return x;
    }
    else
    {

        for(int bit = 15; bit >= 0; bit--)
        {
            if(bit != 0)
            {
                if(care[dp[bit][x]] == care[dp[bit][y]] && care[dp[bit - 1][x]] != care[dp[bit - 1][y]])
                        return query(dp[bit - 1][x], dp[bit - 1][y]);
            }
            else
            {
                 if(dp[bit][y] == dp[bit][x])
                    return dp[bit][y];
            }

        }
    }*/

    while(nivel_lant[care[x]] > nivel_lant[care[y]])
    {
   //     cout << x << " ";
        x = boss[care[x]];

    }
 //   cout << x << " ";
 //   cout << endl;
    while(nivel_lant[care[y]] > nivel_lant[care[x]])
    {
     //   cout << y << " ";
        y = boss[care[y]];
    }
  //  cout << y << " ";
    if(care[x] == care[y])
    {
        if(nivel[x] > nivel[y])
            return y;
        else
            return x;
    }
    int carex = care[x];
    int carey = care[y];
    for(int bit = 12; bit >= 0; bit--)
    {
        if(bit != 0)
        {
            if(dp[bit][carex] == dp[bit][carey] && dp[bit - 1][carex] != dp[bit - 1][carey])
            {
                return query(dp[bit - 1][carex], dp[bit - 1][carey]);
            }
        }
        else
        {
            if(dp[bit][carex] == dp[bit][carey])
                return dp[bit][carey];
        }

    }

}

void debug()
{
    g << "-----------DEBUG-----------" << endl;
    g << "LANTURI:" << '\n';
    for(int i = 1; i <= k; i++)
    {
        g << "Lant " << i << ": ";
        for(int j = 0; j < lant[i].size(); j++)
            g << lant[i][j] << " ";
        g << "Boss-ul: " << boss[i] << " Nivelul: " << nivel_lant[i];
        g << endl;
    }
    g << "DINAMICA AIA BLANAO: " << '\n';
    for(int j = 0 ; j < 5; j++)
    {
        for(int i = 1; i <= k; i++)
            g << "Lantul: " << i << " stramosul: " << (1 << j) << " " << dp[j][i] << endl;
        g << endl;
    }

}

void nivel_lant_brut()
{
    for(int i = 0 ; i <= k; i++)
    {
        int aux = boss[i];
        while(aux != 0)
        {
            aux = boss[care[aux]];
            nivel_lant[i]++;
        }
    }
}


int main()
{
    int n, m;
    f >> n >> m;
    v.resize(n + 2);
    lant.resize(n + 2);
    for(int i = 2; i <= n; i++)
    {
        int x;
        f >> x;
        tati[i] = x;
        v[x].push_back(i);
        lg[i] = lg[i>>1] + 1;

    }
    DFS(1, 0);
    k--;
    care[0] = care[1];
    for(int i = 1; i <= k; i++)
    {
        dp[0][i] = boss[i];
    }
    creez_dinamica(k);
    nivel_lant_brut();
   // debug();
    for(int i = 0 ; i < m ;i++)
    {
        int x, y, rezultat;
        f >> x >> y;
        rezultat = query(x, y) ;
        if(rezultat == 0)
            g << 1 << '\n';
        else
            g << rezultat << '\n';

    }
}