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

#define dmax 100002
#define lgdmax 20
#define x first
#define y second
#define mp make_pair
#define pb push_back
#define sz size()

using namespace std;


int n, m;
typedef pair<int, int> pi;
vector <pi> euler;
vector <int> v[dmax];
int mq[lgdmax][2*dmax+2], poz[dmax];

void read();
void euler_path(int nod, int lvl);
int rmq(int x, int y);
void make_rmq();


void read()
{
    int a, b;
    freopen("lca.in", "r", stdin);
    freopen("lca.out", "w", stdout);
    scanf("%i %i", &n, &m);
    for(int i=2; i<=n; i++)
    {
        scanf("%i", &a);
        v[a].pb(i);

    }

    euler.pb(mp(0,0));
    euler_path(1,1);
    make_rmq();

    int l, m2;

    for(int i=1; i<=m; i++)
    {
        scanf("%i %i", &a, &b);
        if(a==b)printf("%i\n", b);
        else{

        a=poz[a];
        b=poz[b];

        m2=max(a,b);
        a=min(a, b);

        l=log2(m2-a);

        if(euler[mq[l][a]].y<euler[mq[l][m2-(1<<l)]].y)
            b=euler[mq[l][a]].x;
        else b=euler[mq[l][m2-(1<<l)]].x;

        printf("%i\n", b);
        }
    }
}


void make_rmq()
{
    const int lge=euler.sz-1;
    for(int i=0; i<=lge; i++)
        mq[0][i]=i;

    for(int i=1; (1<<i)<=lge; i++)
        for(int j=1; j+(1<<i)-1<=lge; j++)
        {
            if(euler[mq[i-1][j]].y<euler[mq[i-1][j+(1<<(i-1))]].y)
                mq[i][j]=mq[i-1][j];
            else mq[i][j]=mq[i-1][j+(1<<(i-1))];
        }

}


void euler_path(int nod, int lvl)
{

    euler.pb(mp(nod, lvl));
    poz[nod]=euler.sz-1;
    if(v[nod].sz!=0)
    {
        for(int i=0; i<v[nod].sz; i++)
        {
            euler_path(v[nod][i],lvl+1);
            euler.pb(mp(nod, lvl));

        }

    }

}

int main()
{
    read();
    return 0;
}