#include <fstream>
#include <vector>
#include <algorithm>
using namespace std;

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

int n,m,k;
vector<int> adj[100005];
int level[100005];
int euler[200005];
int first_occ[100005];
int lg2[200005];
int rmq[18][200005];

void dfs(int node,int lvl) {
    level[node]=lvl;
    k++;
    euler[k]=node;
    first_occ[node]=k;
    for (int child:adj[node]) {
        dfs(child,lvl+1);
        k++;
        euler[k]=node;
    }
}

int get_min(int node1,int node2) {
    if (level[node1]<level[node2]) return node1;
    return node2;
}

void build_rmq() {
    for (int i=2; i<=k; i++) {
        lg2[i]=lg2[i/2]+1;
    }
    for (int i=1; i<=k; i++) {
        rmq[0][i]=euler[i];
    }
    for (int i=1; (1<<i)<=k; i++) {
        for (int j=1; j+(1<<i)-1<=k; j++) {
            rmq[i][j]=get_min(rmq[i-1][j],rmq[i-1][j+(1<<(i-1))]);
        }
    }
}

int query_lca(int u,int v) {
    int l=first_occ[u];
    int r=first_occ[v];
    if (l>r) swap(l,r);
    int len=r-l+1;
    int j=lg2[len];
    return get_min(rmq[j][l],rmq[j][r-(1<<j)+1]);
}

int main() {
    cin>>n>>m;
    for (int i=2; i<=n; i++) {
        int parent;
        cin>>parent;
        adj[parent].push_back(i);
    }
    dfs(1,1);
    build_rmq();
    for (int i=1; i<=m; i++) {
        int u,v;
        cin>>u>>v;
        cout<<query_lca(u,v)<<'\n';
    }
}