#include <bits/stdc++.h>
#define LOG 17
#define NMAX 100005

using namespace std;

ifstream f("lca.in");
ofstream g("lca.out");

int n, Q, depth[NMAX], up[NMAX][LOG + 1];
bitset <NMAX> v;
vector <int> Muchii[NMAX];

void dfs(int nod)
{
    v[nod] = 1;
    for(auto child : Muchii[nod])
        if(!v[child])
        {
            depth[child] = depth[nod] + 1;

            up[child][0] = nod;
            for(int i = 1; i <= LOG; i++)
                up[child][i] = up[up[child][i - 1]][i - 1];
            dfs(child);
        }
}

int lca(int a, int b)
{
    if(depth[a] < depth[b])
        swap(a, b);

    int k = depth[a] - depth[b];
    for(int i = LOG; i >= 0; i--)
        if(k & (1 << i))
            a = up[a][i];

    if(a == b)
        return a;
    for(int i = LOG; i >= 0; i--)
        if(up[a][i] != up[b][i])
        {
            a = up[a][i];
            b = up[b][i];
        }
    return up[a][0];
}

int main()
{

    f >> n >> Q;

    for(int i = 2; i <= n; i++)
    {
        int x;
        f >> x;
        Muchii[x].push_back(i);
    }

    dfs(1);

    for(int i = 1, x, y; i <= Q; i++)
    {
        f >> x >> y;
        g << lca(x, y) << "\n";
    }

    return 0;
}