#include <cstdio>
#include <cmath>
#include <vector>
#include <algorithm>

using namespace std;

#define NMAX 100010
#define NMAX_Log 30
#define NMAX_Euler 200010
#define Enode(x) Euler[x].first
#define Edepth(x) Euler[x].second

int N;
int FirstInEuler[NMAX];
int ST[NMAX][NMAX_Log];

vector < int > G[NMAX];
vector < pair < int , int > > Euler;

void ConstructEulerPath(int n, int lvl)
{
    Euler.push_back(make_pair(n,lvl));
    FirstInEuler[n] = Euler.size() - 1;

    for(vector < int > :: iterator it = G[n].begin(); it!=G[n].end(); it++)
    {
        ConstructEulerPath(*it,lvl+1);
        Euler.push_back(make_pair(n,lvl));
    }
}

void ConstructSpareTable()
{
    for(int i=1;i<Euler.size();i++)
        ST[i][0] = i;

    for(int j=1; (1<<j) <Euler.size(); j++)
        for(int i=1;i + (1<<j) <= Euler.size();i++)
        {
            int minOnFirstSegment,minOnSecondSegment;
            minOnFirstSegment = ST[i][j-1];
            minOnSecondSegment = ST[i + (1<<(j-1))][j-1];

            if(Edepth(minOnFirstSegment) <= Edepth(minOnSecondSegment))
                ST[i][j] = minOnFirstSegment;
            else
                ST[i][j] = minOnSecondSegment;
        }
}

int LCA(int i , int j)
{
    int a,b;
    a = FirstInEuler[i];
    b = FirstInEuler[j];

    if(a>b)
        swap(a,b);

    int lg = (int) log2(double(b - a + 1));
    int minOnFirstSegment,minOnSecondSegment;

    minOnFirstSegment = ST[a][lg];
    minOnSecondSegment = ST[b - (1<<lg) + 1][lg];

    if(Edepth(minOnFirstSegment) <= Edepth(minOnSecondSegment))
        return Enode(minOnFirstSegment);
    return Enode(minOnSecondSegment);
}

int main()
{
    freopen("lca.in","r",stdin);
    freopen("lca.out","w",stdout);

    int M,x,y;
    scanf("%d%d",&N,&M);
    for(int i=2;i<=N;i++)
    {
        scanf("%d",&x);
        G[x].push_back(i);
    }

    Euler.push_back(make_pair(0,0));
    ConstructEulerPath(1,0);
    ConstructSpareTable();

    while(M--)
    {
        scanf("%d%d",&x,&y);
        printf("%d\n",LCA(x,y));
    }

    return 0;
}