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

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

#define NMAX 100005

vector<int> G[NMAX];

int dp[20][4 * NMAX];
int euler[2 * NMAX], nivel[2 * NMAX];
int primul[NMAX], log2[2 * NMAX];

void dfs(int nod, int niv, int &k)
{
    euler[++k] = nod;
    nivel[k] = niv;
    primul[nod] = k;

    for (auto it : G[nod])
    {
        dfs(it, niv + 1, k);

        euler[++k] = nod;
        nivel[k] = niv;
    }
}

void rmq(int k)
{
    log2[1] = 0;
    for (int i = 2; i <= k; ++i)
        log2[i] = log2[i / 2] + 1;

    for (int i = 1; i <= k; ++i)
        dp[0][i] = i;

    for (int i = 1; (1 << i) <= k; ++i)
        for (int j = 1; j <= k - (1 << i) + 1; ++j)
        {
            int putere = 1 << (i - 1);

            if (nivel[dp[i - 1][j]] < nivel[dp[i - 1][j + putere]])
                dp[i][j] = dp[i - 1][j];
            else
                dp[i][j] = dp[i - 1][j + putere];
        }
}

int lca(int x, int y)
{
    int a = primul[x], b = primul[y];

    if (a > b)
    {
        int aux = a;
        a = b;
        b = aux;
    }

    int dif = b - a + 1;
    int log = log2[dif];
    int putere = (1 << log);

    if (nivel[dp[log][a]] < nivel[dp[log][b - putere + 1]])
        return euler[dp[log][a]];
    else
        return euler[dp[log][b - putere + 1]];
}

int main()
{
    int n, m;
    fin >> n >> m;

    for (int i = 2; i <= n; ++i)
    {
        int x;
        fin >> x;
        G[x].push_back(i);
    }

    int k = 0;
    dfs(1, 0, k);

    rmq(k);

    for (int i = 1; i <= m; ++i)
    {
        int x, y;
        fin >> x >> y;

        fout << lca(x, y) << '\n';
    }
    return 0;
}