#include <bits/stdc++.h>
#define ll long long
#define ull unsigned long long
#define ld long double
#define chad char
#define mod 10'007
#define dim 100005
#define lim 1000000
#define BASE 67
#define NMAX 1505
#define FOR(i,a,b) for(int i=(a); i<=(b); i++)
#define pli pair<ll,int>
#define pil pair<int,ll>
#define piii pair<int,pair<int,int> >
#define pii pair<int,int>
#define pll pair<ll,ll>
#define pb push_back
#define mp make_pair
#define nr_biti __builtin_popcount
using namespace std;

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

int n,q;
vector<int> g[dim];
int h[dim];
int e[2*dim];
int rmq[20][2*dim];
int timer;
int st[dim];
int lg[dim];

void dfs(int nod,int daddy=0)
{
    h[nod]=1+h[daddy];
    st[nod]=++timer;
    e[timer]=nod;

    for(auto it:g[nod])
    {
        if(it==daddy)
            continue;

        dfs(it,nod);
        e[++timer]=nod;
    }
}

void pre()
{
    for(int i=1; i<=timer; i++)
        rmq[0][i]=e[i];

    lg[0]=-1;

    for(int i=1; i<=timer; i++)     
        lg[i]=1+lg[i/2];

    for(int i=1; (1<<i)<=timer; i++)
        for(int j=1; j<=timer-(1<<i)+1; j++)
        {
            int l(1<<(i-1));

            if(h[rmq[i-1][j]]<h[rmq[i-1][j+l]])
                rmq[i][j]=rmq[i-1][j];
            else 
                rmq[i][j]=rmq[i-1][j+l];
        }
}

int lca(int x,int y)
{
    int diff=abs(st[x]-st[y])+1;    
    int l=lg[diff];
    int sh=diff-(1<<l);

    if(h[rmq[l][min(st[x],st[y])]]<h[rmq[l][min(st[x],st[y])+sh]])
        return rmq[l][min(st[x],st[y])];
    else 
        return rmq[l][min(st[x],st[y])+sh];
}

int main()
{
    ios_base::sync_with_stdio(false);
    fin.tie(nullptr);
    fout.tie(nullptr);

    fin >> n >> q;

    for(int i=2; i<=n; i++)
    {
        int x;
        fin >> x;

        g[x].pb(i);
        g[i].pb(x);
    }

    dfs(1);
    pre();

    while(q--)
    {
        int x,y;

        fin >> x >> y;

        fout << lca(x,y) << "\n";
    }

    return 0;
}