#include <fstream>
#include <vector>

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

const int NMAX = 100005;
const int LGMAX = 18;

vector<int> v[NMAX], roots;
int anc[NMAX][LGMAX];
int in[NMAX], out[NMAX];
int timp, n;

void dfs(int nod, int t) {
    anc[nod][0] = t;
    for (int j = 1; j < LGMAX; j++) {
        anc[nod][j] = anc[anc[nod][j - 1]][j - 1];
    }

    in[nod] = ++timp;
    for (auto i: v[nod]) {
        dfs(i, nod);
    }
    out[nod] = timp;
}

int solve(int nod, int k) {
    for (int i = 0; (1 << i) <= k; i++) {
        if (k & (1 << i)) {
            nod = anc[nod][i];
        }
    }

    return nod;
}

bool esteStramos(int a, int b) {
    if (a == 0) {
        return true;
    }

    return in[a] <= in[b] && out[b] <= out[a];
}

int lca(int a, int b) {
    int st = 0, dr = n, ans = n;

    while (st <= dr) {
        int m = (st + dr) / 2;

        if (esteStramos(solve(a, m), b)) {
            ans = m;
            dr = m - 1;
        } else {
            st = m + 1;
        }
    }

    return solve(a, ans);
}

int main() {
    int q;
    cin >> n >> q;

    for (int i = 2; i <= n; i++) {
        int a; cin >> a;

        v[a].push_back(i);
    }

    dfs(1, 0);

    for (int i = 1; i <= q; i++) {
        int a, b; cin >> a >> b;

        cout << lca(a, b) << '\n';
    }

    return 0;
}