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

using namespace std;

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

#define lim 100010
int rmq[20][2*lim], depth[lim], dad[lim], lg[2*lim], poz[lim];
vector <int> G[lim];
int n, m, k;

void euler (int nod)
{
    depth[nod] = depth[dad[nod]] + 1;
    rmq[0][++k] = nod;
    poz[nod] = k;
    for (auto it:G[nod])
    {
        euler(it);
        rmq[0][++k] = nod;
    }
}


int main()
{
    int x,y,dist;
    fin>>n>>m;
    for (int i=2; i<=n; i++)
    {
        fin>>dad[i];
        G[dad[i]].push_back(i);
    }
    euler(1);
    lg[0] = -1; /////////// !!!!
    for (int i=1; i<=k; i++)
        lg[i] = lg[i/2] + 1;


    for (int j=1; (1<<j)<=k; j++)
        for (int i=1; i+(1<<j)-1 <= k; i++)
        {
            if (depth[rmq[j-1][i]] < depth[rmq[j-1][i+(1<<(j-1))]])
                rmq[j][i] = rmq[j-1][i];
            else    rmq[j][i] = rmq[j-1][i+(1<<(j-1))];
        }


    for (int i=1; i<=m; i++)
    {
        fin>>x>>y;
        x = poz[x];
        y = poz[y];
        if (x>y)    swap (x,y);
        dist = lg[y-x+1];
        if (depth[rmq[dist][x]] < depth[rmq[dist][y-(1<<dist)+1]])
            fout<<rmq[dist][x]<<'\n';
        else
            fout<<rmq[dist][y-(1<<dist)+1]<<'\n';
    }

    fin.close();
    fout.close();
    return 0;
}