#include <iostream>
#include <vector>

using namespace std;

constexpr char nl = '\n';
const int NMAX = 1e5;
const int LOG = 20;

vector<int> v[NMAX];
int binLog[2 * NMAX + 5];
int sptbl[2 * NMAX + 5][LOG];
int euler[2 * NMAX + 5], depth[2 * NMAX + 5];
int first[NMAX + 5];
int cnt = 0;

void dfs(int node, int dep) {
    first[node] = cnt;
    euler[cnt] = node;
    depth[cnt] = dep;
    ++cnt;

    for (auto x: v[node]) {
        dfs(x, dep + 1);
        euler[cnt] = node;
        depth[cnt] = dep;
        ++cnt;
    }
}

int query(int l, int r) {
    int len = r - l + 1;
    int k = binLog[len];
    if (depth[sptbl[l][k]] < depth[sptbl[r - (1 << k) + 1][k]]) {
        return sptbl[l][k];
    } else {
        return sptbl[r - (1 << k) + 1][k];
    }
}

int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);
    cout.tie(nullptr);

    freopen("lca.in", "r", stdin);
    freopen("lca.out", "w", stdout);

    int n, q;
    cin >> n >> q;
    for (int i = 2; i <= n; ++i) {
        int x;
        cin >> x;
        v[x].push_back(i);
    }

    binLog[1] = 0;
    for (int i = 2; i <= 2 * n; ++i) {
        binLog[i] = binLog[i / 2] + 1;
    }

    dfs(1, 0);

    for (int i = 0; i < cnt; ++i ) {
        sptbl[i][0] = i;
    }

    for (int j = 1; j < LOG; ++j) {
        for (int i = 0; i + (1 << j) <= cnt; ++i) {
            if (depth[sptbl[i][j - 1]] < depth[sptbl[i + (1 << (j - 1))][j - 1]]) {
                sptbl[i][j] = sptbl[i][j - 1];
            } else {
                sptbl[i][j] = sptbl[i + (1 << (j - 1))][j - 1];
            }
        }
    }

    while (q--) {
        int x, y;
        cin >> x >> y;
        int left = min(first[x], first[y]);
        int right = max(first[x], first[y]);
        int index = query(left, right);
        cout << euler[index] << nl;
    }
    return 0;
}