#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)
using namespace std;

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

int n,m,tin[200005],tout[200005],lca[200005][20],par[200005];
vector<int>nod[200005];

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

int lowca(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 j=1;j<=18;j++){
            if(lca[x][j]==0 || (tin[lca[x][j]]<tin[y] && tout[lca[x][j]]>tout[y])==true){
                x=lca[x][j-1];
                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=1;i<n;i++){
        int x;
        fin >> x;
        nod[x].push_back(i+1);
        par[i+1]=x;
        lca[i+1][0]=x;
    }
    for(int i=1;i<=19;i++){
        for(int j=1;j<=n;j++) lca[j][i]=lca[lca[j][i-1]][i-1];
    }
    int curr=0;
    DFS(1,curr);
    for(int i=1;i<=m;i++){
        int x,y;
        fin >> x >> y;
        fout << lowca(x,y) << '\n';
    }
    return 0;
}