#include <fstream>
#include <vector>
#define NMAX 100002
using namespace std;
ifstream  fin("lca.in");
ofstream fout("lca.out");
int n,m,tata[NMAX],nivel[NMAX],up[NMAX][18];
vector<int> tree[NMAX];

void citire()
{
    fin>>n>>m;

    for(int i=2; i<=n; i++)
    {
        fin>>tata[i];
        tree[tata[i]].push_back(i);
    }
}

void DFS(int nod)
{
    for(int i=0; i<tree[nod].size(); i++)
    {
        int next_nod=tree[nod][i];

        nivel[next_nod]=nivel[nod]+1;
        up[next_nod][0]=nod;

        for(int j=1; j<=17; j++)
        {
            up[next_nod][j]=up[up[next_nod][j-1]][j-1];
        }

        DFS(next_nod);
    }
}

int lca(int a, int b)
{
    if(nivel[b]>nivel[a])
    {
        swap(a,b);
    }

    int k=nivel[a]-nivel[b];
    for(int j=17; j>=0; j--)
    {
        if(k&(1<<j))
        {
            a=up[a][j];
        }
    }

    if(a==b)
    {
        return a;
    }

    for(int j=17; j>=0; j--)
    {
        if(up[a][j]!=up[b][j])
        {
            a=up[a][j];
            b=up[b][j];
        }
    }

    return up[a][0];
}

int main()
{
    citire();

    DFS(1);

    int a,b;
    for(int i=1; i<=m; i++)
    {
        fin>>a>>b;

        fout<< lca(a,b) << "\n";
    }

    return 0;
}