#include <bits/stdc++.h>

using namespace std;
ifstream f("lca.in");
ofstream g("lca.out");
int n,q;
int poz[100005],lv[100005],Log[200005];
bool sel[100005];
vector <int> G[100005],par;
pair<int,int> rmq[25][200005];
void dfs(int x, int level)
{
    poz[x]=par.size();
    lv[x]=level;
    par.push_back(x);
    for(auto it : G[x])
    {
        dfs(it,level+1);
        par.push_back(x);
    }
}
void construct_rmq()
{
    int l=par.size()-1;
    for(int i=2;i<=l;i++)
    {
        Log[i]=1+Log[i/2];
    }
    for(int i=1;i<=l;i++)
    {
        rmq[0][i]={lv[par[i]],par[i]};
    }
    for(int i=1;i<=Log[l];i++)
    {
        for(int j=1;j<=l;j++)
        {
            if(rmq[i-1][j].first<rmq[i-1][j+(1<<(i-1))].first)
            {
                rmq[i][j]=rmq[i-1][j];
            }
            else
            {
                rmq[i][j]=rmq[i-1][j+(1<<(i-1))];
            }
        }
    }
}
int query(int x, int y)
{
    int k=y-x+1;
    k=Log[k];
    if(rmq[k][x]<rmq[k][y-(1<<k)+1])
    {
        return rmq[k][x].second;
    }
    return rmq[k][y-(1<<k)+1].second;
}
int main()
{
    f>>n>>q;
    for(int i=2;i<=n;i++)
    {
        int x;
        f>>x;
        G[x].push_back(i);
    }
    par.push_back(0);
    dfs(1,1);
    construct_rmq();
    for(int i=1;i<=q;i++)
    {
        int x,y;
        f>>x>>y;
        if(poz[x]>poz[y])
        {
            swap(x,y);
        }
        g<<query(poz[x],poz[y])<<'\n';
    }
    return 0;
}