#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 = 17;

int n, m, i, j, lim, dif, lca, x, y, lev[nmax], f[lmax][nmax];

vector<int> v[nmax];

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

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", &f[0][i]);
        v[f[0][i]].pb(i);
    }

    for(i = 1; (1 << i) <= n; i++)
        for(j = 1; j <= n; j++)
            f[i][j] = f[i - 1][f[i - 1][j]];

    lim = i - 1;
    dfs(1);

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

        if(lev[x] > lev[y])
            swap(x, y);

        dif = lev[y] - lev[x];

        for(i = 0; (1 << i) <= dif; i++)
            if((1 << i) & dif)
                y = f[i][y];

        if(x == y)
            lca = x;
        else
        {
            for(i = lim; i >= 0; i--)
                if(f[i][x] != f[i][y])
                {
                    x = f[i][x];
                    y = f[i][y];
                }

            lca = f[0][x];
        }

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

    return 0;
}