#include <bits/stdc++.h>
#define NUM 100005
int level[NUM << 1];
int euler[NUM << 1];
int lg2[NUM << 1];
int first[NUM];
int sparse[NUM << 2][20];
int n, m, k;
using namespace std;
vector <int> G[NUM];
ifstream f("lca.in");
ofstream g("lca.out");

void read()
{
    f >> n >> m;
    for(int i = 2; i <= n; ++i)
    {
        int x;
        f >> x;

        G[x].push_back(i);
    }
}

void dfs(int node, int lev)
{
    euler[++k] = node;
    level[k] = lev;
    first[node] = k;

    for(auto son : G[node])
    {
        dfs(son, lev + 1);

        euler[++k] = node;
        level[k] = lev;
    }
}

void rmq()
{
    for(int i = 2; i <= k; ++i)
        lg2[i] = lg2[i >> 1] + 1;
    for(int i = 1; i <= k; ++i)
        sparse[i][0] = i;

    for(int j = 1; (j << 1) < k; ++j)
        for(int i = 1; i + (j << 1) <= k; ++i)
        {
            int aux = 1 << (j - 1);
            sparse[i][j] = sparse[i][j - 1];
            if(level[sparse[i][j]] > level[sparse[i + aux][j - 1]])
                sparse[i][j] = sparse[i + aux][j - 1];
        }
}

int lca(int x, int y)
{
    int a = first[x];
    int b = first[y];
    if(a > b)
        swap(a, b);
    int diff = b - a + 1;
    int ldiff = lg2[diff];
    int sol = sparse[a][ldiff];
    if(level[sol] > level[sparse[b - (1 << ldiff) + 1][ldiff]])
        sol = sparse[b - (1 << ldiff) + 1][ldiff];
    return euler[sol];
}

int main()
{
    read();
    dfs(1, 0);
    rmq();

    while(m--)
    {
        int x, y;
        f >> x >> y;
        g << lca(x, y) << "\n";
    }
    f.close();
    g.close();
}