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

FILE *f = freopen("lca.in", "r", stdin);
FILE *g = freopen("lca.out", "w", stdout);

const int N_MAX = 100001;
int n, m, nr;

int lg[2 * N_MAX];
int rmq[20][2 * N_MAX];
int P[2 * N_MAX];
int first[N_MAX];
int nivel[2 * N_MAX];

vector <int> G[N_MAX];

void read()
{
    scanf("%d %d", &n, &m);

    for (int i=1; i<n; i++)
    {
        int x;
        scanf("%d", &x);
        G[x].push_back(i+1);
    }
}

void init()
{
    for (int i=2; i<=nr; i++) lg[i] = lg[i/2] + 1;
}

void Euler(int nod, int k)
{
    P[++nr] = nod;
    first[nod] = nr;
    nivel[nr] = k;

    for (int i : G[nod])
    {
        Euler(i, k+1);
        P[++nr] = nod;
        nivel[nr] = k;
    }
}

void RMQ()
{
    for (int i=1; i<=nr; i++)
        rmq[0][i] = i;

    for (int i=1; (1<<i) < nr; i++)
    {
        for (int j=1; j<= nr - (1<<i) + 1; j++)
        {
            int l = 1<<(i-1);
            rmq[i][j] = rmq[i-1][j];

            if (nivel[rmq[i-1][j]] > nivel[rmq[i-1][j+l]])
                rmq[i][j] = rmq[i-1][j+l];
        }
    }
}

int lca(int x, int y)
{
    int first_x = first[x];
    int first_y = first[y];

    if (first_x > first_y)
        swap(first_x, first_y);

    int diff = first_y - first_x + 1;

    int log = lg[diff];
    int put = 1<<log;

    int ans = rmq[log][first_x];

    if (nivel[rmq[log][first_x]] > nivel[rmq[log][first_y - put + 1]])
        ans = rmq[log][first_y - put + 1];

    return P[ans];
}

void solve()
{
    for (int i=1; i<=m; i++)
    {
        int x, y;
        scanf("%d %d", &x, &y);
        printf("%d\n", lca(x, y));
    }
}

int main()
{
    read();
    Euler(1, 0);
    init();
    RMQ();
    solve();
    return 0;
}