#include<cstdio>
#include<vector>
#include<cmath>
#include<algorithm>
#define NMax 100005
using namespace std;

int first[NMax],eu[2*NMax];
int niv[2*NMax],m[2*NMax][20];
vector <int> a[NMax];
int k,n,mm;

void citire ()
{
    int i,x;
    scanf("%d%d",&n,&mm);
    for (i=2; i<=n; i++)
    {
        scanf("%d",&x);
        a[x].push_back(i);
    }
}

void df_euler (int nod, int lev)
{
    eu[++k]=nod;
    niv[k]=lev;
    first[nod]=k;
    for (int i=0; i<a[nod].size(); i++)
    {
        df_euler(a[nod][i],lev+1);
        eu[++k]=nod;
        niv[k]=lev;
    }
}

void rmq ()
{
    int i,j,aux;
    for (i=1; i<=k; i++)
        m[i][0]=i;
    for (j=1; (1<<j)<k; j++)
        for (i=1; i+(1<<j)-1<=k; i++)
        {
            aux=1<<(j-1);
            m[i][j]=m[i][j-1];
            if (niv[m[i][j]] > niv[m[i+aux][j-1]])
               m[i][j]=m[i+aux][j-1];
        }
}

int lca (int x, int y)
{
    int p1,p2,ka,sol;
    p1=first[x]; p2=first[y];
    if (p1>p2) swap(p1,p2);
    ka=log10(p2-p1+1)/log10(2);
    sol=m[p1][ka];
    if (niv[m[p2-(1<<ka)+1][ka]]<niv[sol])
        sol=m[p2-(1<<ka)+1][ka];
    return eu[sol];
}

int main ()
{
    freopen("lca.in","r",stdin);
    freopen("lca.out","w",stdout);
    int x,y;
    citire();
    df_euler(1,0);
    rmq();
    for (int i=1; i<=mm; i++)
    {
        scanf("%d%d",&x,&y);
        printf("%d\n",lca(x,y));
    }
    return 0;
}