#include<bits/stdc++.h>
using namespace std;
#define INIT  ios_base :: sync_with_stdio(false); fin.tie(NULL); fout.tie(NULL);mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
#define mp make_pair
#define pb push_back
#define ft first
#define sc second
#define ll long long
#define pii pair<int, int>
#define count_bits __builtin_popcount
#define pow pw
int n,m;

ifstream fin("lca.in"); ofstream fout("lca.out");
#define cin fin
#define cout fout
int p[18][100010];
vector<int> g[100010];
int ent[100010], ex[100010];
int t=1;

void dfs(int s){
    ent[s]=t;
    t++;

for(int i:g[s]){
    dfs(i);
}
ex[s]=t;
t++;
return;
}




int LCA(int u, int v){
int w=u;
if(ex[v]<ex[u]){swap(u, v);}
if(u==v){return u;}
if( (ex[u]>=ent[v]) && (ent[u]<=ent[v]) ){
    return u;
}
if(ex[v]>=ent[u] && (ent[v]<=ent[u]) ){
    return v;
}

while(true){
    for(int j=0; j<=17; j++){

        if( (ex[p[j][u]]<ent[v]) && (p[j][u]!=0) ){
            u=p[j][u];
        }
        else{
            if(j==0){break;}
            goto Next;
        }
    }
    break;
    Next:continue;
}
return p[0][u];
}





int32_t main(){
INIT
cin>>n>>m;
for(int i=1; i<n; i++){
    cin>>p[0][i+1];
    g[p[0][i+1] ].pb(i+1);
}

for(int s=1; s<=n; s++){
    for(int j=1; j<=20;j++){
    if(p[j-1][p[j-1][s] ]==0){break;}
    p[j][s]=p[j-1][p[j-1][s] ];
}

}


dfs(1);

/*for(int i=0; i<tour.size(); i++){cout<<tour[i].sc<<" ";}
cout<<"\n";*/
for(int i=1; i<=m; i++){
    int u,v;
    cin>>u>>v;
    cout<<LCA(u, v)<<"\n";
}



return 0;
}