#include <bits/stdc++.h>

using namespace std;
ifstream fin ("lca.in");
ofstream fout ("lca.out");
int n,m,i,j,k,h[100001*2],l[100001*2],first[100001],x,y,d[100001][20],a,b,p;
vector <int> g[100001];
void dfs (int nod, int nivel)
{
    h[++k]=nod;
    l[k]=nivel;
    first[nod]=k;
    for (int i=0;i<g[nod].size();i++)
    {
        dfs(g[nod][i],nivel+1);
        h[++k]=nod;
        l[k]=nivel;
    }
}

void rmq()
{
    for (i=1;i<=k;i++) d[i][0]=i;
    for (j=1;(1<<j)<=k;j++)
    {
        for (i=1;i+(1<<j)-1<=k;i++)
        {
           if (l[d[i][j-1]]<l[d[i+(1<<(j-1))][j-1]]) d[i][j]=d[i][j-1];
           else d[i][j]=d[i+(1<<(j-1))][j-1];
        }
    }
}
int lca(int x, int y)
{
    a=first[x];
    b=first[y];
    if (a>b) swap(a,b);
    p=log2(b-a+1);
    if (l[d[a][p]]<l[d[b-(1<<p)+1][p]]) return h[d[a][p]];
    return h[d[b-(1<<p)+1][p]];

}
int main()
{
    fin>>n>>m;
    for (i=2;i<=n;i++)
    {
        fin>>x;
        g[x].push_back(i);
    }
    dfs(1,0);
    rmq();

    for (i=1;i<=m;i++)
    {
        fin>>x>>y;
        fout<<lca(x,y)<<'\n';
    }

    return 0;
}