#include <fstream>
#include <algorithm>
#include <queue>
#include <vector>
using namespace std;
ifstream cin("lca.in");
ofstream cout("lca.out");
vector<vector<int>> graph;
vector<int> level,parent,sol;
void bfs(int start)
{
    queue<int> q; q.push(start); level[start]=0;
    while(!q.empty())
    {
        int node=q.front(); q.pop();
        for(int neighbor:graph[node])
        {
            if(level[neighbor]==-1){
                level[neighbor]=level[node]+1;
                q.push(neighbor);
            }
        }
    }
}
int back_(int node,int l)
{
    while(level[node]>l)node=parent[node];
    return node;
}
int main()
{
    int n,m; cin>>n>>m;
    graph.resize(n+1,vector<int>());
    parent.resize(n+1);
    level.resize(n+1,-1); parent[1]=1;
    for(int i=1;i<n-1;i++){
        int x;cin>>x; parent[i+1]=x;
        graph[x].push_back(i+1);
        graph[i+1].push_back(x);
    }
    int x; cin>>x; graph[x].push_back(n);
    graph[n].push_back(x); parent[n]=x;
    bfs(1);
    for(int i=1;i<=m;i++)
    {
        int a,b; cin>>a>>b; int n1,n2;
        if(level[a]>level[b])
        {
            n1=b;
            n2=back_(a,level[b]);
        }
        else if(level[a]<level[b]){
            n1=a; n2=back_(b,level[a]);
        }else {
    n1=a; n2=b;
    } int lca;
        while(true)
        {
            if(n1==n2) {
                lca=n1; break;
            }
            n1=parent[n1];
            n2=parent[n2];
        }
        sol.push_back(lca);
    }
    for(int s:sol) cout<<s<<'\n';
    return 0;
}