#include <fstream>
#include <vector>
#define pb push_back
#define TR(C, i)\
    for(typeof(C.begin()) i = C.begin(); i != C.end(); i++)

using namespace std;

const int nmax = 100100;
int N, M, RMQ[20][nmax << 2], Lg[nmax << 1];
vector <int> A[nmax];

ifstream in("lca.in");

void read()
{
    in >> N >> M;
    int i, a;
    for(i = 2; i <= N; i++)
    {
        in >> a;
        A[a].pb( i );
    }
}

int H[nmax << 1], V[nmax << 1], cat;
int First[nmax];

void euler(int nod, int lev)
{
    H[++cat] = lev;
    V[cat] = nod;
    First[nod] = cat;

    TR(A[nod], it)
    {
        euler(*it, lev + 1);
        V[++cat] = nod;
        H[cat] = lev;
    }
}

void create()
{
    euler(1, 1);

    int i, j, up;
    for(i = 2; i <= cat; i++)
        Lg[i] = Lg[i >> 1] + 1;

    for(i = 1; i <= cat; i++)
        RMQ[0][i] = i;

    for(i = 1; (1 << i) < cat; i++)
        for(j = 1; j <= cat - (1 << i); j++)
        {
            up = 1 << (i - 1);
            RMQ[i][j] = RMQ[i - 1][j];
            if(H[RMQ[i][j]] > H[RMQ[i - 1][j + up]])
                RMQ[i][j] = RMQ[i - 1][j + up];
        }
}

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

    int diff = First[b] - First[a] + 1;
    int lg = Lg[diff];
    int add = diff - (1 << lg);
    int Mic = RMQ[lg][First[a]];

    if(H[Mic] > H[RMQ[lg][First[a] + add]])
        Mic = RMQ[lg][First[a] + diff - (1 << lg)];
    return V[Mic];
}

void query()
{
    ofstream out("lca.out");

    int i, a, b;
    for(i = 1; i <= M; i++)
    {
        in >> a >> b;
        out << lca(a, b) << '\n';
    }
}


int main()
{
    read();
    create();
    query();
    return 0;
}