#include <fstream>
#include <vector>
#include <algorithm>
using namespace std;

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

const int MAXN = 1e5+5;
int n, m, N;
vector<int> adj[MAXN];
int lev[MAXN];
int E[2 * MAXN];
int pos[MAXN];
int lg2[2 * MAXN];
int rmq[18][2 * MAXN];

void Dfs(int x, int lv)
{
    lev[x] = lv;
    E[++N] = x;
    pos[x] = N;
    for (int y : adj[x])
    {
        Dfs(y, lv + 1);
        E[++N] = x;
    }
}

int get_min(int x, int y)
{
    if (lev[x] < lev[y]) return x;
    return y;
}

void Rmq()
{
    for (int i = 2; i <= N; ++i)
        lg2[i] = lg2[i / 2] + 1;

    for (int i = 1; i <= N; ++i)
        rmq[0][i] = E[i];

    for (int i=1; (1 << i) <= N; ++i)
        for (int j = 1; j + (1 << i) <= N; ++j)
            rmq[i][j] = get_min(rmq[i - 1][j], rmq[i - 1][j + (1 << (i - 1))]);
}

int LCA(int x, int y)
{
    int px = pos[x];
    int py = pos[y];
    if (px > py) swap(px, py);

    int k = lg2[py - px + 1];
    return get_min(rmq[k][px], rmq[k][py - (1 << k) + 1]);
}

int main()
{
    cin >> n >> m;
    for (int i = 2; i <= n; ++i)
    {
        int fa;
        cin >> fa;
        adj[fa].push_back(i);
    }
    Dfs(1, 1);
    Rmq();
    for (int i = 1, x, y; i <= m; ++i)
    {
        cin >> x >> y;
        cout << LCA(x, y) << '\n';
    }
}