#include<fstream>
#include<vector>
#include<string>
#define modulo 666013

using namespace std;

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


const int NMAX = 100005;
const int LMAX = 20;

int i, n, k, j,st,dr,sol,x,y,m,tata;
vector <int> v[NMAX];
int euler[4 * NMAX], nivel[4 * NMAX], viz[NMAX], first[NMAX],lg[2 * NMAX];
int rmq[LMAX][4 * NMAX];



void dfs(int nod, int level)
{
    viz[nod] = 1;
    euler[++k] = nod;
    nivel[k] = level;
    first[nod] = k; // prima aparitie a lui nod in parcurgerea Euler

    for(int i = 0; i < v[nod].size(); i++)
    {
        int fiu = v[nod][i];
        if(viz[fiu] == 0)
        {
            dfs(fiu, level + 1);
            euler[++k] = nod;
            nivel[k] = level;
        }
    }
}

void rangeMinimQuery()
{
    lg[1] = 0;
    for(int i = 2; i <= k; ++i)
        lg[i] = lg[i / 2] + 1;
    for(int i = 1; i <= k; ++i)
        rmq[0][i] = i;

    for(int i = 1; (1 << i) < k; ++i)
        for(int j = 1; j <= k - (1 << i); ++j)
        {
            int middle = 1 << (i - 1);

            rmq[i][j] = rmq[i - 1][j];
            if(nivel[rmq[i-1][j + middle]] < nivel[rmq[i][j]])
                rmq[i][j] = rmq[i-1][j + middle];
        }
}

int lca(int x, int y)
{
    int a, b, sol;
    a = first[x];
    b = first[y];
    if(a > b)
        swap(a, b);
    int k = lg[b - a];
    sol = rmq[k][a];
    if(nivel[rmq[k][b - (1 << k) + 1]] < nivel[sol])
    {
        sol = rmq[k][b - (1 << k) + 1];
    }
    return euler[sol];
}

int main()
{
    fin >> n >> m;
    for(i = 2; i <= n; i++)
    {
        fin >> tata;
        v[tata].push_back(i);
    }
    dfs(1, 0);
    rangeMinimQuery();
    for(i = 1; i <= m; i++)
    {
        fin >> x >> y;
        fout << lca(x, y) << "\n";
    }
}