#include <fstream>
#include <vector>
#include <cmath>

using namespace std;

vector <vector <int>> fii;
vector <vector <int>> s;
vector <int> t_in;
vector <int> t_out;
int timp;
int log_2_n;

void dfs(int x)
{
    t_in[x] = ++timp;
    for (auto y: fii[x])
    {
        dfs(y);
    }
    t_out[x] = ++timp;
}

bool e_stramos(int x, int y)
{
    return (t_in[x] <= t_in[y] && t_out[y] <= t_out[x]);
}

int lca(int x, int y)
{
    if (e_stramos(x, y))
    {
        return x;
    }
    for (int i = log_2_n; i >= 0; i--)
    {
        if (s[i][x] != 0 && !e_stramos(s[i][x], y))
        {
            x = s[i][x];
        }
    }
    return s[0][x];
}

int main()
{
    ifstream in("lca.in");
    ofstream out("lca.out");
    int n, q;
    in >> n >> q;
    log_2_n = (int)log2(n);
    fii.resize(n + 1);
    s.resize(log_2_n + 1);
    t_in.resize(n + 1);
    t_out.resize(n + 1);
    for (int i = 0; i <= log_2_n; i++)
    {
        s[i].resize(n + 1, 0);
    }
    for (int j = 2; j <= n; j++)
    {
        int t_j;
        in >> t_j;
        s[0][j] = t_j;
        fii[t_j].push_back(j);
    }
    for (int i = 1; i <= log_2_n; i++)
    {
        for (int j = 1; j <= n; j++)
        {
            s[i][j] = s[i-1][s[i-1][j]];
        }
    }
    timp = 0;
    dfs(1);
    for (int i = 0; i < q; i++)
    {
        int x, y;
        in >> x >> y;
        out << lca(x, y) << "\n";
    }
    in.close();
    out.close();
    return 0;
}