#include <bits/stdc++.h>
#define ll long long
#define all(a) (a).begin(), (a).end()
#pragma GCC optimize("O3")
#pragma GCC optimize("Ofast")
#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,tune=native")
#define sz() size()
#define fr first
#define sc second
#define pb push_back
#define er erase
#define in insert
#define pi pair<int,int>
#define pii pair<pair<int,int>,int>
#define mp make_pair
#define int long long
#define rc(s) return cout<<s,0
#define rcc(s) cout<<s,exit(0)
///#define cin fin
///#define cout fout
using namespace std;

const int mod=1e9+7;
const int modp=1999999973;

int n,m,x,y,lca[100005][19],tin[100005],tout[100005];
vector<int>nod[100005];

void DFS(int s,int &curr){
    tin[s]=curr;
    for(auto it:nod[s]){
        curr++;
        DFS(it,curr);
    }
    curr++;
    tout[s]=curr;
}


int lcaa(int x,int y){
    if(tin[x]<tin[y] && tout[x]>tout[y]) return x;
    if(tin[y]<tin[x] && tout[y]>tout[x]) return y;
    while((tin[lca[x][0]]<tin[y] && tout[lca[x][0]]>tout[y])==false){
        for(int i=0;i<=17;i++){
            if((tin[lca[x][i]]<tin[y] && tout[lca[x][i]]>tout[y])==false && (tin[lca[x][i+1]]<tin[y] && tout[lca[x][i+1]]>tout[y])==true){
                x=lca[x][i];
                break;
            }
        }
    }
    return lca[x][0];
}

int32_t main(){
	//ios_base::sync_with_stdio(false);cin.tie(0);cerr.tie(0);cout.tie(0);
    srand(chrono::steady_clock::now().time_since_epoch().count());
    ifstream fin("lca.in");
    ofstream fout("lca.out");
    fin >> n >> m;
    for(int i=2;i<=n;i++){
        fin >> x;
        nod[x].push_back(i);
        lca[i][0]=x;
    }
    for(int i=1;i<=17;i++){
        for(int j=1;j<=n;j++){
            lca[j][i]=lca[lca[j][i-1]][i-1];
        }
    }
    int pop=1;
    DFS(1LL,pop);
    for(int i=1;i<=m;i++){
        fin >> x >> y;
        fout << lcaa(x,y) << '\n';
    }
}