// CTI
 
#include <cstdio>
#include <algorithm>
#include <vector>
#include <cmath>z
 
using namespace std;
 
vector <int> a[1000002];
int t[100002], l[100002], tata[100002]; // tata in arbore, nivel, tata sectiune precedenta
 
int mod;    // dimensiune sectiune

 
void dfs(int nod, int tnod, int nivel) {
    l[nod]    = nivel;
    if (nivel < mod) {  // prima sectiune - tata este radacina
        tata[nod] = 1;
    } else {
        if (nivel % mod) {  // inceputul sectiunii
            tata[nod] = tnod;
        } else {
            tata[nod] = tata[tnod];
        }
    }
 
    for (int i = 0; i < a[nod].size(); ++i) {
        dfs(a[nod][i], nod, nivel + 1);
    }
}
 
int LCA(int x, int y) {
    while (tata[x] != tata[y]) {    // cautam sectiunea
        if (l[x] > l[y]) {
            x = tata[x];
        } else {
            y = tata[y];
        }
    }
 
    while (x != y) {                // cautam tatal in arbore
        if (l[x] > l[y]) {
            x = t[x];
        } else {
            y = t[y];
        }
    }
 
    return x;
}
 
int main()
{
    freopen("lca.in","r",stdin);
    freopen("lca.out","w",stdout);
 
    int n, q;
    scanf("%d%d", &n, &q);
    mod = 180;
    for (register int i = 2; i <= n; ++i) {
        scanf("%d", &t[i]);
        a[t[i]].push_back(i);
    }
 
    dfs(1, 0, 0);
 
    for (register int i = 0; i < q; ++i) {
        int x, y;
        scanf("%d%d", &x, &y);
        printf("%d\n", LCA(x, y));
    }
 
    return 0;
}