#include <fstream>
#include <vector>
#define nmax 100002
#define lgmax 100
using namespace std;
ifstream fin("lca.in");
ofstream fout("lca.out");

int ap[nmax],lev[nmax*2],repr[nmax*2],lg[nmax*3];
int rmq[lgmax][nmax],cont=0;

vector <int> graf[nmax];

void dfs(int nod,int level)
{
    repr[++cont]=nod;
    lev[cont]=level;
    ap[nod]=cont;
    int lng=graf[nod].size();
    for(int i=0;i<lng;i++)
    {
        dfs(graf[nod][i],level+1);

        repr[++cont]=nod;
        lev[cont]=level;
    }
}

int main()
{
    int n,m,x,y;
    fin>>n>>m;
    for(int i=2;i<=n;i++)
    {
        fin>>x;
        graf[x].push_back(i);
    }
    dfs(1,0);
    for(int i=2;i<=cont;i++)
        lg[i]=lg[i/2]+1;
    for(int i=1;i<=cont;i++)
        rmq[0][i]=i;
    for(int i=1;(1<<i)<cont;i++)
        for(int j=1;j<=cont-(1<<i);j++)
        {
            rmq[i][j]=rmq[i-1][j];
            if(lev[rmq[i-1][j+(1<<i-1)]]<lev[rmq[i][j]])
                rmq[i][j]=rmq[i-1][j+(1<<i-1)];
        }
    for(int i=1;i<=m;i++)
    {
        fin>>x>>y;
        int a=ap[x];
        int b=ap[y];
        if(a>b)
        {
            int aux=a;
            a=b;
            b=aux;
        }
        int sol=rmq[lg[b-a+1]][a];
        if(lev[sol]>lev[rmq[lg[b-a+1]][b+1-(1<<lg[b-a+1])]])
            sol=rmq[lg[b-a+1]][b+1-(1<<lg[b-a+1])];
        fout<<repr[sol]<<"\n";
    }
    return 0;
}