// solutie de 70p cu binary lifting
#include <bits/stdc++.h>
#define fi first
#define se second 
#define ll long long

using namespace std;

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

const int LOG = 17;
const int N = 1e5 + 5;

int n, m;
// dad[i][j] -> al 2^j lea parinte in sus pentru nodul i, dad[i][0] este parintele direct al lui i
int dad[N][18];
int depth[N];
vector<int> v[N];

void dfs(int node, int dad = 0) {
    depth[node] = depth[dad] + 1;
    
    for (auto child : v[node]) {
        if (!depth[child]) {
            dfs(child, node);
        }
    }
}

void build_ancestors() {
    for (int bit = 1; bit < LOG; bit++) {
        for (int node = 1; node <= n; node++) {
            dad[node][bit] = dad[dad[node][bit - 1]][bit - 1];
        }
    }
}

int get_lca(int x, int y) {
    if (depth[x] < depth[y]) {
        swap(x, y);
    }

    for (int bit = LOG; bit >= 0; bit--) {
        if ((1 << bit) & (depth[x] - depth[y])) {
            x = dad[x][bit];
        }
    }

    for (int bit = LOG; bit >= 0; bit--) {
        if (dad[x][bit] != dad[y][bit]) {
            x = dad[x][bit];
            y = dad[y][bit];
        }
    }

    return (x == y ? x : dad[x][0]);
}

int main() {
    in >> n >> m;
    for (int i = 2, x; i <= n; i++) {
        in >> x;
        dad[i][0] = x;
        v[x].push_back(i);
    }

    dfs(1);
    build_ancestors();

    for (int x, y; m--; ) {
        in >> x >> y;
        out << get_lca(x, y) << '\n';
    }
    
    return 0;
}