#include <fstream>
#include <vector>

using namespace std;

#define MAX_N 100005
#define MAX_L 20



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

int N, M, T[MAX_L][MAX_N], Lg[MAX_N], Lev[MAX_N];
vector <int> G[MAX_N];

void citire()
{
    fin >> N >> M;

    for(int i = 2; i <= N; ++i)
    {
        fin >> T[0][i];
        G[T[0][i]].push_back(i);
    }

    int k;
    for(k = 1; (1 << k) <= N; ++k)
        for(int i = 1; i <= N; ++i)
            T[k][i] = T[k-1][T[k-1][i]];
}

void dfs(int nod, int lev)
{
    Lev[nod] = lev;

    for(auto it:G[nod])
        dfs(it, lev+1);
}

int lca(int x, int y)
{
    if(Lev[x] < Lev[y])
        swap(x, y);

    int log1, log2;
    for(log1 = 1; (1 << log1) < Lev[x]; ++log1);
    for(log2 = 1; (1 << log2) < Lev[y]; ++log2);

    for(int k = log1; k >= 0; --k)
        if(Lev[x] - (1 << k) >= Lev[y])
            x = T[k][x];

    if(x == y) return x;

    for(int k = log2; k >= 0; --k)
        if(T[k][x] && T[k][x] != T[k][y])
            x = T[k][x],
            y = T[k][y];

    return T[0][x];
}

int main()
{
    citire();
    dfs(1, 0);

    while(M--)
    {
        int x, y;
        fin >> x >> y;
        fout << lca(x, y) << "\n";
    }
}