#include <fstream>
#include <vector>

#define nMax 100001
#define log2Max 20
#define nrElMax 200003
#define pb push_back

using namespace std;

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

int n, nrQueryMax, nrEl, nrQuery;
int rmq[log2Max][nrElMax], First[nMax], Lev[nMax], log2[nrElMax];
vector<int> G[nMax];

void dfs(int node)
{
    rmq[0][++nrEl]=node;
    First[node]=nrEl;

    for(vector<int>::iterator it=G[node].begin(); it!=G[node].end(); it++)
    {
        int fiu=*it;
        Lev[fiu]=Lev[node]+1;
        dfs(fiu);
        rmq[0][++nrEl]=node;
    }
}

void rangeMinimumQuery()
{
    for(int i=2; i<=nrEl; i++)
        log2[i]=log2[i/2]+1;

    for(int len=1; (1 << len)<=nrEl; len++)
    {
        int diff=(1 << (len-1));
        for(int i=1; i+(1 << len)-1<=nrEl; i++)
        {
            rmq[len][i]=rmq[len-1][i];
            if(Lev[rmq[len-1][i+diff]]<Lev[rmq[len][i]])
                rmq[len][i]=rmq[len-1][i+diff];
        }
    }
}

int query(int a, int b)
{
    if(a>b)
        swap(a, b);
    int len=log2[b-a+1];
    int diff=(1 << len);

    int Sol=rmq[len][a];
    if(Lev[rmq[len][b-diff+1]]<Lev[Sol])
        Sol=rmq[len][b-diff+1];
    return Sol;
}

void solve()
{
    int a, b;
    Lev[1]=1;
    dfs(1);

    rangeMinimumQuery();
    for(int i=1; i<=nrQuery; i++)
    {
        fin>>a>>b;
        fout<<query(First[a], First[b])<<'\n';
    }
}
int main()
{
    int a;
    fin>>n>>nrQuery;
    for(int i=2; i<=n; i++)
    {
        fin>>a;
        G[a].pb(i);
    }
    solve();
}