#include <fstream>
#include <vector>

using namespace std;

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

const int Dim = 100002;
int n, m, nr;
int E[2 * Dim], niv[2 * Dim], pos[Dim], log2[2 * Dim], r[2 * Dim][20];
using VI = vector <int>;
using VVI = vector < VI >;

VVI G;

void DFS(int x, int nv);
int LCA(int x, int y);
void RMQ();

int main() {

    fin >> n >> m;
    G = VVI(n+1);
    for(int i = 2, x; i <= n; ++i) {
        fin >> x;
        G[x].push_back(i);
    }

    for(int i = 2; i < 2 * Dim; ++i)
        log2[i] = log2[i / 2] + 1;

    DFS(1, 1);
    RMQ();

    for(int i = 1, x, y; i <= m; ++i) {
        fin >> x >> y;
        fout << LCA(x, y) << "\n";
    }


    return 0;
}

void DFS(int x, int nv) {
    ++nr;
    E[nr] = x, niv[nr] = nv, pos[x] = nr;
    for(const int & y : G[x]) {
        DFS(y, nv + 1);
        ++nr;
        E[nr] = x, niv[nr] = nv;
    }
}


void RMQ() {
     n = 2 * n - 1;
    for(int i = 1; i <= n; ++i)
        r[i][0] = i;

    for(int j = 1; (1 << j) <= n; ++j)
        for(int i = 1; i + (1 << j) - 1 <= n; ++i)
        {
            if (niv[r[i][j - 1]] < niv[r[i + (1 << (j - 1))][j - 1]])
                r[i][j] = r[i][j - 1];
            else
				r[i][j] = r[i + (1 << (j - 1))][j - 1];
        }
}

int LCA(int x, int y) {
    x = pos[x], y = pos[y];

    if(x > y)
        swap(x, y);
    int k = log2[y - x  + 1];

    if(niv[r[x][k]] < niv[r[y - (1 << k) + 1][k]])
        return E[r[x][k]];
    return E[r[y - (1 << k) + 1][k]];
}