#include <fstream>
#include <vector>

using namespace std;

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

const int NMAX = 1e5 + 1;
const int L = 16;
int ti[NMAX], to[NMAX], timp, t[L + 1][NMAX], emax[NMAX];
vector <int> fii[NMAX];

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

bool este_stramos(int x, int y)
{
    return(ti[x] <= ti[y] && to[y] <= to[x]);
}

int lca(int x, int y)
{
    if (este_stramos(x, y))
    {
        return x;
    }
    for (int e = emax[x]; e >= 0; e--)
    {
        if (t[e][x] != 0 && !este_stramos(t[e][x], y))
        {
            x = t[e][x];
        }
    }
    return t[0][x];
}

int main()
{
    int n, m;
    in >> n >> m;
    for (int i = 2; i <= n; i++)
    {
        in >> t[0][i];
        fii[t[0][i]].push_back(i);
    }
    for (int e = 1; (1 << e) <= n; e++)
    {
        for (int i = 1; i <= n; i++)
        {
            t[e][i] = t[e - 1][t[e - 1][i]];
            if (t[e][i] != 0)
            {
                emax[i] = e;
            }
        }
    }
    dfs(1);
    for (int i = 0; i < m; i++)
    {
        int x, y;
        in >> x >> y;
        out << lca(x, y) << "\n";
    }
    return 0;
}