#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>

using namespace std;

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

int n, q, i, j, p, x, y, cnt, l, dif, lca;
int lev[nmax], first[nmax];
int euler[2 * nmax], rmq[lmax][2 * nmax];

vector<int> v[nmax];

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

    for(auto it : v[x])
    {
        lev[it] = lev[x] + 1;
        dfs(it);
        euler[++cnt] = x;
    }
}
int main()
{
    freopen("lca.in", "r", stdin);
    freopen("lca.out", "w", stdout);

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

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

    lev[1] = 1;
    dfs(1);

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

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

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

        x = first[x];
        y = first[y];
        if(x > y) swap(x, y);

        dif = y - x + 1;
        l = log2(dif + 0.5);
        p = 1 << l;

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

        printf("%d\n", lca);
    }
    return 0;
}