#include <iostream>
#include <fstream>
#include <vector>
#include <algorithm>
using namespace std;
vector<vector<int>>tree;
ifstream fin("lca.in");
ofstream fout("lca.out");
const int LOGMAX = 19;//log2(10^5)
const int NMAX = 1e5+1;
int anc[NMAX][LOGMAX];//anc[i][j]=nodul care se afla 2^j in sus fata de nodul i
vector<int>depth;
void CalcAnc(int crt,int depthCrt, int father) {
    depth[crt] = depthCrt;
    anc[crt][0] = father;
    for (int i = 1; i <= depthCrt; ++i) {
        int up = anc[crt][i - 1];
        anc[crt][i] = anc[up][i - 1];
    }
    for (int i = 0; i < tree[crt].size(); ++i) {
        if (tree[crt][i] != father) {
            CalcAnc(tree[crt][i], depthCrt + 1, crt);
        }
    }
}


int cb(int u, int v) {

    for (int i = LOGMAX-1; i >= 0; --i) {
        if (anc[u][i] !=anc[v][i]) {
            u = anc[u][i];
            v = anc[v][i];
        }
    }

    return anc[u][0];
}
int BinaryLifting(int u, int v) {

    if (depth[u] < depth[v]) {
        swap(u, v);
    }

    for (int i = LOGMAX-1; i >=0; --i) {
        if (depth[u] - (1 << i) >= depth[v]) {
            u = anc[u][i];
        }
    }

    if (u == v) {
        return v;
    }
    return cb(u, v);
}

int main()
{
    int n,q;
    fin >> n>>q;
    int father;
    depth.resize(n+1);
    tree.resize(n + 1);
    for (int i = 2; i <= n; ++i) {
        fin >> father;
        tree[father].push_back(i);
        tree[i].push_back(father);
    }
    CalcAnc(1, 0, 0);
    int u, v;
    while (q)
    {
        fin >> u >> v;
        fout << BinaryLifting(u, v) << "\n";
        q--;
    }
    return 0;
}
//=^..^=