#include <fstream>
#include <vector>

using namespace std;

int N, M, stramos[30][100010], nivel[100010];
vector <int> G[100010];

void dfs(int nod, int lev) {
    nivel[nod] = lev;

    for(vector<int>::iterator it = G[nod].begin(); it != G[nod].end(); ++it)
        dfs(*it, lev+1);
}

int lca(int x, int y) {
    if(nivel[x] < nivel[y])
        swap(x, y);

    int log1, log2;
    for(log1 = 1; (1 << log1) < nivel[x]; ++log1);
    for(log2 = 1; (1 << log2) < nivel[y]; ++log2);

    for(int k = log1; k >= 0; --k) {
        if(nivel[x] - (1 << k) >= nivel[y])
            x = stramos[k][x];
    }
    if(x == y)
        return x;

    for(int k = log2; k >= 0; --k) {
        if(stramos[k][x] && stramos[k][x] != stramos[k][y]) {
            x = stramos[k][x];
            y = stramos[k][y];
        }
    }
    return stramos[0][x];
}

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

    in >> N >> M;

    for(int i = 2; i <= N; ++i) {
        in >> stramos[0][i];
        G[stramos[0][i]].push_back(i);
    }

    int k;
    for(k = 1; (1 << k) <= N; ++k) {
        for(int i = 1; i <= N; ++i) {
            stramos[k][i] = stramos[k-1][stramos[k-1][i]];
        }
    }
    dfs(1, 0);

    while(M--) {
        int x, y;
        in >> x >> y;
        out << lca(x, y) << "\n";
    }
}