#include <bits/stdc++.h>

using namespace std;

const int max_size = 1e5 + 20, rmax = 22;

int lvl[max_size], poz[max_size], rmq[rmax][2 * max_size], lg[2 * max_size], timp;
vector <int> mc[max_size];

void dfs (int nod)
{
    timp++;
    poz[nod] = timp;
    rmq[0][timp] = nod;
    for (auto f : mc[nod])
    {
        lvl[f] = lvl[nod] + 1;
        dfs(f);
        rmq[0][++timp] = nod;
    }
}

bool cmp (int x, int y)
{
    return lvl[x] < lvl[y];
}

void solve ()
{
    int n, q;
    cin >> n >> q;
    for (int i = 2; i <= n; i++)
    {
        int x;
        cin >> x;
        mc[x].push_back(i);
    }
    dfs(1);
    for (int i = 2; i <= timp; i++)
    {
        lg[i] = lg[i / 2] + 1;
    }
    for (int e = 1; e < rmax; e++)
    {
        for (int i = 1; i + (1 << e) - 1 <= timp; i++)
        {
            rmq[e][i] = min(rmq[e - 1][i], rmq[e - 1][i + (1 << (e - 1))], cmp);
        }
    }
    while (q--)
    {
        int x, y;
        cin >> x >> y;
        x = poz[x];
        y = poz[y];
        if (x > y)
        {
            swap(x, y);
        }
        int diff = y - x + 1, e = lg[diff];
        cout << min(rmq[e][x], rmq[e][y - (1 << e) + 1], cmp) << '\n';
    }
    cout << '\n';
}

signed main ()
{
#ifdef LOCAL
    freopen("test.in", "r", stdin);
    freopen("test.out", "w", stdout);
#else
    freopen("lca.in", "r", stdin);
    freopen("lca.out", "w", stdout);
#endif // LOCAL
    ios_base::sync_with_stdio(false);
    cin.tie(0);
    cout.tie(0);
    long long tt;
    //cin >> tt;
    tt = 1;
    while (tt--)
    {
        solve();
    }
    return 0;
}