#include <fstream>
#include <vector>

using namespace std;
ifstream cin("lca.in");
ofstream cout("lca.out");
vector<vector<int>>vt(100001,vector<int>());
int fpoz[100001],cnt=0;///poz in v
struct NA
{
    int nod,adancime;
};
vector<NA>v;
void dfs(int nod,int adanc=0)
{
    //cout<<nod<<" ";
    NA a;
    a.nod=nod;
    a.adancime=adanc;
    v.push_back(a);
    fpoz[nod]=cnt;
    cnt++;
    for(auto i=vt[nod].begin(); i!=vt[nod].end(); i++)
    {
        dfs(*i,adanc+1);
        //cout<<nod<<" ";
        v.push_back(a);
        fpoz[nod]=cnt;
        cnt++;
    }
}
int lg2[400001],pw2[40];
NA rmq[40][400001];
int main()
{
    pw2[0]=1;
    lg2[1]=1;
    for(int i=1; i<32; i++)
        pw2[i]=pw2[i-1]*2;
    int n,m,max1=0,a,b;
    cin>>n>>m;
    for(int i=2; i<=n; i++)
    {
        cin>>a;
        vt[a].push_back(i);
    }
    dfs(1);
    int sz=v.size();
    for(int i=2; i<=sz; i++)
        lg2[i]=lg2[i/2]+1;
                //cout<<lg2[7]<<" "<<pw2[2]<<'\n';
    for(int i=0; i<sz; i++)
    {
        rmq[0][i]=v[i];
        //cout<<rmq[0][i].nod<<" ";
    }
    //cout<<'\n';
    for(int i=1; i<lg2[sz]; i++)
        for(int j=0; j<sz; j++)
        {
            rmq[i][j]=rmq[i-1][j];
            if(j+pw2[i-1]<sz && rmq[i][j].adancime>rmq[i-1][j+pw2[i-1]].adancime)
                rmq[i][j]=rmq[i-1][j+pw2[i-1]];
                //cout<<rmq[i][j].nod<<" ";
                //if(j==sz-1)cout<<'\n';
        }
        for(int i=0;i<m;i++)
        {
            cin>>a>>b;///lca de a,b
            if(a==b){cout<<a<<'\n';continue;}
            int pa=fpoz[a],pb=fpoz[b];
            if(pa>pb)swap(pa,pb);
            //cout<<pa<<" * "<<pb<<'\n';
            NA min1=rmq[lg2[pb-pa]-1][pa];
            if(rmq[lg2[pb-pa]-1][pa].adancime>rmq[lg2[pb-pa]-1][pb-pw2[lg2[pb-pa]-1]+1].adancime)
                min1=rmq[lg2[pb-pa]-1][pb-pw2[lg2[pb-pa]-1]+1];
            cout<<min1.nod<<'\n';
        }
    return 0;
}
/**
        for(auto i=v.begin(); i!=v.end(); i++)
            cout<<(*i).nod<<" ";cout<<'\n';
        for(auto i=v.begin(); i!=v.end(); i++)
            cout<<(*i).adancime<<" ";  RMQ
20 10
1 1 1 1 2 5 7 3 2 9 6 4 6 2 10 15 6 14 11
9 14
10 9
15 15
1 17
3 3
3 1
11 14
18 19
12 2
16 14


            */