#include <iostream>
#include <fstream>
#include <vector>
#include <cmath>

const int MAXN = 100000 + 5;
const int MAXLOG = log2(MAXN);

using namespace std;

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

int n,intrebari;
int dp[MAXN][MAXLOG + 5],inaltime[MAXN];
vector<int>graf[MAXN];


void dfs(int nod){
    for(int i = 0; i < graf[nod].size(); i++){
        int curent = graf[nod][i];
        inaltime[curent] = inaltime[nod] + 1;
        dfs(curent);
    }
}

int main()
{
    in>>n>>intrebari;
    inaltime[1] = 1;
    for(int i = 2; i <= n; i++){
        int nod;
        in>>nod;
        dp[i][0] = nod;
        graf[nod].push_back(i);
    }
    dfs(1);
    for(int put = 1; put < MAXLOG; put++){
        for(int i = 2; i <= n; i++){
            dp[i][put] = dp[dp[i][put - 1]][put - 1];
        }
    }
    for(int i = 1; i <= intrebari; i++){
        int nod1,nod2;
        in>>nod1>>nod2;
        int put = MAXLOG,stramos;
        /// eu vreau ca nod1 sa fie mai jos in graf decat nod2 adica ca inaltime[nod1] > inaltime[nod2]
        if(inaltime[nod1] < inaltime[nod2])
            swap(nod1,nod2);/// daca nu este asa cum vreau eu, schimb nod1 si nod2
        while(inaltime[nod1] != inaltime[nod2])
            nod1 = dp[nod1][0];
        while(put >= 0){
            if(dp[nod1][put] && dp[nod2][put] && dp[nod1][put] != dp[nod2][put]){
                nod1 = dp[nod1][put];
                nod2 = dp[nod2][put];
            }
            if(put == 0)
                break;
            put /= 2;
        }

        if(nod1 != nod2)
            out<<dp[nod1][0];
        else
            out<<nod1;
        out<<"\n";;
    }

    return 0;
}