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

using namespace std;

const int MAXN = 100000;
const int LOG = 17; // 2^17 este mai mare decât 100000
vector<int> g[MAXN + 1];
int depth[MAXN + 1], parent[MAXN + 1][LOG + 1];

void dfs(int node, int par) {
    depth[node] = depth[par] + 1;
    parent[node][0] = par;
    for (int i = 1; i <= LOG; i++) {
        parent[node][i] = parent[parent[node][i - 1]][i - 1];
    }
    for (int child : g[node]) {
        if (child != par) {
            dfs(child, node);
        }
    }
}

int lca(int u, int v) {
    if (depth[u] < depth[v]) {
        swap(u, v);
    }
    for (int i = LOG; i >= 0; i--) {
        if (depth[u] - (1 << i) >= depth[v]) {
            u = parent[u][i];
        }
    }
    if (u == v) {
        return u;
    }
    for (int i = LOG; i >= 0; i--) {
        if (parent[u][i] != parent[v][i]) {
            u = parent[u][i];
            v = parent[v][i];
        }
    }
    return parent[u][0];
}

int main() {
    ifstream fin("lca.in");
    ofstream fout("lca.out");

    int n, m;
    fin >> n >> m;
    for (int i = 2; i <= n; i++) {
        int p;
        fin >> p;
        g[p].push_back(i);
        g[i].push_back(p);
    }

    dfs(1, 0);

    for (int i = 0; i < m; i++) {
        int u, v;
        fin >> u >> v;
        fout << lca(u, v) << '\n';
    }

    fin.close();
    fout.close();
    return 0;
}