#include <fstream>
#include <vector>

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

using namespace std;

const int MAXLOG = 16;

vector<vector<int>> RMQ;
vector<int> Height;
int N,Q;

void read()
{
    fin >> N >> Q;
    RMQ.resize(MAXLOG+1,vector<int>(N+1,0));
    Height.resize(N+1,0);

    RMQ[0][1] = 1;
    for(int i = 2; i <= N; ++i)
        fin >> RMQ[0][i];
}
int getH(int nod)
{
    if(RMQ[0][nod] == nod)
        return Height[nod] = 1;
    if(Height[nod] == 0)
        return (Height[nod] = getH(RMQ[0][nod]) + 1);
    return Height[nod];
}
void build_RMQ()
{
    for(int i = 1; i <= N; ++i)
        getH(i);
    for(int len = 1; len <= MAXLOG; ++len)
        for(int i = 1; i <= N; ++i)
            RMQ[len][i] = RMQ[len-1][RMQ[len-1][i]];
}
int LCA(int u,int v)
{
    if(Height[u] < Height[v])
        swap(u,v);

    for(int len = MAXLOG; len >= 0; --len)
        if(Height[u] - (1 << len) >= Height[v])
            u = RMQ[len][u];

    if(u == v)
        return u;

    for(int len = MAXLOG; len >= 0; --len)
        if(RMQ[len][u] && RMQ[len][u] != RMQ[len][v])
        {
            u = RMQ[len][u];
            v = RMQ[len][v];
        }
    return RMQ[0][u];
}
int main()
{
    ios::sync_with_stdio(false);
    fin.tie(0);

    read();
    build_RMQ();

    int x,y;
    while(Q--)
    {
        fin >> x >> y;
        fout << LCA(x,y) << '\n';
    }
}