#include<cstdio>
#include<fstream>
#include<iostream>
#include<iomanip>
#include<algorithm>
#include<vector>
#include<bitset>
#include<deque>
#include<queue>
#include<set>
#include<map>
#include<cmath>
#include<cstring>
#include<ctime>
#include<cstdlib>
#include<unordered_map>

#define ll long long
#define pb push_back
#define mp make_pair
#define pii pair<int,int>
#define pll pair<ll,ll>
#define all(x) (x).begin(), (x).end()
#define fi first
#define se second

using namespace std;

const int nmax = 100005;
const int lmax = 18;

int n, m, i, j, p, x, y, N, dif, lca, lev[nmax], first[nmax], lg[2 * nmax], euler[2 * nmax], rmq[lmax][2 * nmax];

vector<int> v[nmax];

void dfs(int x)
{
    euler[++N] = x;
    first[x] = N;

    for(auto it : v[x])
    {
        lev[it] = lev[x] + 1;
        dfs(it);
        euler[++N] = x;
    }
}

int main()
{
    freopen("lca.in", "r", stdin);
    freopen("lca.out", "w", stdout);

    scanf("%d%d", &n, &m);

    for(i = 2; i <= n; i++)
    {
        scanf("%d", &x);
        v[x].pb(i);
    }

    dfs(1);

    for(i = 2; i <= N; i++)
        lg[i] = lg[i / 2] + 1;

    for(i = 1; i <= N; i++)
        rmq[0][i] = euler[i];

    for(i = 1, p = 2; p <= N; i++, p *= 2)
        for(j = 1; j + p - 1 <= N; j++)
        {
            rmq[i][j] = rmq[i - 1][j];
            if(lev[rmq[i - 1][j + p / 2]] < lev[rmq[i - 1][j]])
                rmq[i][j] = rmq[i - 1][j + p / 2];
        }

    for(; m; m--)
    {
        scanf("%d%d", &x, &y);

        x = first[x];
        y = first[y];

        if(x > y)
            swap(x, y);

        dif = y - x;
        dif = lg[dif];
        p = 1 << dif;

        lca = rmq[dif][x];
        if(lev[rmq[dif][y - p + 1]] < lev[rmq[dif][x]])
            lca = rmq[dif][y - p + 1];

        printf("%d\n", lca);
    }

    return 0;
}