#include <fstream>
#include <vector>
#define Nmax 100001
using namespace std;
ifstream f("lca.in");
ofstream g("lca.out");
vector <int> G[Nmax];
int n,x,y,i,Eu[2*Nmax],Niv[2*Nmax],Fst[Nmax],k,log[2*Nmax],m;
int Rmq[20][4*Nmax];
void dfs(int nod,int lvl)
{
    Eu[++k]=nod;
    Niv[k]=lvl;
    Fst[nod]=k;
    vector<int> ::iterator  it;
    for(it=G[nod].begin();it<G[nod].end();it++)
    {
        dfs(*it ,lvl+1);
        Eu[++k]=nod;
        Niv[k]=lvl;
    }
}
void FaRMQ()
{
    log[1]=0;
    for(int i = 2; i <= k; ++i)
        log[i] = log[i >> 1] + 1;
    for(int i = 1; i <= k; ++i)
        Rmq[0][i] = i;

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

            Rmq[i][j] = Rmq[i-1][j];
            if(Niv[Rmq[i-1][j + l]] < Niv[Rmq[i][j]])
                Rmq[i][j] = Rmq[i-1][j + l];
        }
}
int lca(int x, int y)
{
    int diff, l, sol, sh;
    int a = Fst[x], b = Fst[y];
    if(a > b) swap(a, b);
    diff = b - a + 1;
    l = log[diff];
    sol = Rmq[l][a];
    sh = diff - (1 << l);
    if(Niv[sol] > Niv[Rmq[l][a + sh]])
        sol = Rmq[l][a + sh];
    return Eu[sol];
}
int main()
{
    f>>n>>m;
    for(int i=2;i<=n;i++)
    {
        f>>x;
        G[x].push_back(i);
    }
    dfs(1,0);
    FaRMQ();
    for(int i=1;i<=m;i++)
    {
        f>>x>>y;
        g<<lca(x,y)<<'\n';
    }
    return 0;
}