#include <fstream>
#include <vector>

using namespace std;

ifstream fin("lca.in");
ofstream fout("lca.out");

int eu[40][200003],niv[40][200003],aparePoz[100002],k,log[200003],n,m,x,y;

vector <int> G[100003];

void Euler(int poz,int nivel)
{
    k++;
    aparePoz[poz]=k;
    niv[0][k]=nivel;
    eu[0][k]=poz;
    for(vector <int>::iterator it=G[poz].begin();it!=G[poz].end();it++)
    {
        int pz=*it;
        Euler(pz,nivel+1);
        k++;
        niv[0][k]=nivel;
        eu[0][k]=poz;
    }
}


void Rmq()
{
    log[1]=0;
    for(int i=2;i<=k;i++)
        log[i]=log[i/2]+1;
    for(int i=1;i<=log[k];i++)
    {
        for(int j=1;j<=k-(1<<i)+1;j++)
        {
            if(niv[i-1][j]<niv[i-1][j+(1<<(i-1))])
            {
                niv[i][j]=niv[i-1][j];
                eu[i][j]=eu[i-1][j];
            }
            else
            {
                niv[i][j]=niv[i-1][j+(1<<(i-1))];
                eu[i][j]=eu[i-1][j+(1<<(i-1))];
            }
        }
    }
}

int Get_Min(int y,int x)
{
    int lg=log[y-x+1];
    if(niv[lg][x]<niv[lg][y-(1<<lg)+1])
    {
        return eu[lg][x];
    }
    else
    {
        return eu[lg][y-(1<<lg)+1];
    }
}


int main()
{
    fin>>n>>m;
    for(int i=2;i<=n;i++)
    {
        fin>>x;
        G[x].push_back(i);
    }
    Euler(1,0);
    Rmq();
    while(m)
    {
        m--;
        fin>>x>>y;
        if(aparePoz[y]<aparePoz[x])
            swap(x,y);
        fout<<Get_Min(aparePoz[y],aparePoz[x])<<"\n";
    }
    return 0;
}