#include <bits/stdc++.h>
using namespace std;
#define all(x) x.begin(),x.end()
#define pb push_back
using i64=long long;
const int inf=1e9;
const int N=1e5;
const int M=2e6;
vector<int>out,node_query,rez,t;
vector<vector<int>>g,ind;
int n,m;
void init_dsu()
{
    t.resize(n);
    iota(all(t),0);
}
int root(int x)
{
    if(x!=t[x])
    {
        t[x]=root(t[x]);
    }
    return t[x];
}
void unite(int x,int y)
{
    t[root(y)]=root(x);
}

void dfs1(int nod=0)
{
    static int acm=-1;
    for(auto &c:g[nod])
        dfs1(c);
    out[nod]=++acm;
}
void dfs2(int nod=0)
{
    for(auto &c:g[nod])
    {
        dfs2(c);
        unite(nod,c);
    }
    for(auto &c:ind[nod])
    {
        rez[c]=root(node_query[c]);
    }
}
void resize_n()
{
    g.resize(n);
    ind.resize(n);
    out.assign(n,-1);
    init_dsu();
    node_query.assign(m,-1);
    rez.assign(m,-1);
}
main()
{
    ifstream cin("lca.in");
    ofstream cout("lca.out");
    cin>>n>>m;
    resize_n();
    for(int i=1;i<n;i++)
    {
        int x;
        cin>>x;
        g[x-1].pb(i);
    }
    dfs1();
    for(int i=0;i<m;i++)
    {
        int x,y;
        cin>>x>>y;
        x--;
        y--;
        if(out[x]>out[y])
            swap(x,y);
        ind[y].pb(i);
        node_query[i]=x;
    }
    dfs2();
    for(auto &c:rez)
        cout<<c+1<<'\n';
}