#include <fstream>
#include <vector>

using namespace std;

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

const int DIM = 100010;
const int LOG = 20;

int n, m, x, y;
int startPos[DIM], endPos[DIM], currPos = 0;
int father[DIM], ancestor[LOG][DIM];
vector<int> l[DIM];

void dfs(int node, int lvl) {
    startPos[node] = ++currPos;
    for (auto son : l[node])
        dfs(son, lvl + 1);
    endPos[node] = ++currPos;
}

void calcAncestors() {
    for (int i = 1; i <= n; i++)
        ancestor[0][i] = father[i];
    for (int p = 1; p < LOG; p++)
        for (int i = 1; i <= n; i++)
            ancestor[p][i] = ancestor[p - 1][ancestor[p - 1][i]];
}

inline bool isAncestor(int node1, int node2) {
    return startPos[node1] < startPos[node2] && endPos[node2] < endPos[node1];
}

int getLCA(int node1, int node2) {
    if (isAncestor(node1, node2))
        return node1;
    if (isAncestor(node2, node1))
        return node2;

    for (int p = LOG - 1; p >= 0; p--) {
        int node = ancestor[p][node1];
        if (node != 0 && !isAncestor(node, node2))
            node1 = node;
    }
    return ancestor[0][node1];
}

int main() {
    fin >> n >> m;
    for (int i = 2; i <= n; i++) {
        fin >> father[i];
        l[father[i]].push_back(i);
    }

    dfs(1, 0);
    calcAncestors();

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

    return 0;
}