#include<fstream>
#include<vector>
using namespace std;

ifstream cin("lca.in");
ofstream cout("lca.out");

const int NMAX = 1e5 + 10;
const int MAXLOG = 19;

vector<int> vecini[NMAX];
int dp[MAXLOG][2 * NMAX],euler[2 * NMAX],nivel[NMAX],poz[NMAX],e,loga[2 * NMAX];

void dfs(int nod)
{
    euler[++e] = nod;
    poz[nod] = e;

    for(auto it : vecini[nod])
        {
            nivel[it] = nivel[nod] + 1; dfs(it);
            euler[++e] = nod;
        }
}

int lca(int a,int b)
{
    int st = poz[a],dr = poz[b];
    if(st > dr) swap(st,dr);
    int p = loga[dr - st + 1];
    int ans = dp[p][st];
    if(nivel[ans] > nivel[dp[p][dr - (1 << p) + 1]]) ans = dp[p][dr - (1 << p) + 1];
    return ans;
}

int main()
{
    int n,q,a,b; cin >> n >> q;
    for(int i = 2; i <= n ; i++)
        {
            cin >> a;
            vecini[a].emplace_back(i);
        }

    dfs(1); dp[0][1] = euler[1];
    for(int i = 2; i <= e ; i++)
        {
           loga[i] = loga[i / 2] + 1;
           dp[0][i] = euler[i];
        }

    for(int l = 1; l <= loga[e] ; l++)
        {
            for(int i = 1; i + (1 << l) - 1 <= e ; i++)
                {
                    dp[l][i] = dp[l - 1][i];
                    int other = i + (1 << (l - 1));
                    if(nivel[dp[l][i]] > nivel[dp[l - 1][other]]) dp[l][i] = dp[l - 1][other];
                }
        }

    while(q--)
        {
            cin >> a >> b;
            cout << lca(a,b) << '\n';
        }
}