#include <iostream>
#include <fstream>
#include <queue>
#include <vector>

using namespace std;
ifstream in("lca.in");
ofstream out("lca.out");

#define pb push_back
const int NMax = 1e5 + 5;
const int EMax = 2 * NMax;
const int logMax = 20;
const int inf = 2e9 + 5;

int N,M,nrEuler;
int dad[NMax],depth[NMax],poz[NMax],euler[EMax],rmq[EMax][logMax],lg[EMax];
vector<int> v[NMax];

void dfs(int,int);

int main() {
    in>>N>>M;
    for (int i=2;i<=N;++i) {
        in>>dad[i];
        v[dad[i]].pb(i);
    }

    dfs(1,0);

    lg[1] = 0;
    rmq[1][0] = euler[1];
    for (int i=2;i<=nrEuler;++i) {
        lg[i] = lg[i/2] + 1;
        rmq[i][0] = euler[i];
    }

    for (int p=1; (1<<p) <= nrEuler;++p) {
        for (int i=1;i + (1<<p) - 1 <= nrEuler;++i) {
            int nod1 = rmq[i][p-1],
                nod2 = rmq[i+(1<<(p-1))][p-1],
                val = (depth[nod1] < depth[nod2]) ? nod1 : nod2;
            rmq[i][p] = val;
        }
    }

    while (M--) {
        int x,y;
        in>>x>>y;
        if (poz[x] > poz[y]) {
            swap(x,y);
        }

        x = poz[x];
        y = poz[y];

        int pw = lg[y-x+1],
            nod1 = rmq[x][pw],
            nod2 = rmq[y - (1<<pw) + 1][pw],
            val = (depth[nod1] < depth[nod2]) ? nod1 : nod2;

        out<<val<<'\n';
    }
    in.close();out.close();
    return 0;
}

void dfs(int nod,int dad) {
    depth[nod] = depth[dad] + 1;
    euler[++nrEuler] = nod;
    poz[nod] = nrEuler;

    for (int k=0;k < (int)v[nod].size();++k) {
        int next = v[nod][k];
        if (depth[next]) {
            continue;
        }

        dfs(next,nod);
        euler[++nrEuler] = nod;
    }
}