#include <fstream>
#include <vector>
#define nmax 100002
#define lgmax 30
using namespace std;
ifstream fin("lca.in");
ofstream fout("lca.out");

vector <int> graf[nmax];
int h[nmax*2],l[nmax*2],f[nmax],lg[nmax*2];
int rmq[lgmax][nmax*2],k=0;

void dfs(int nod,int lev)
{
    h[++k]=nod;
    l[k]=lev;
    f[nod]=k;
    int lg=graf[nod].size();
    for(int i=0;i<lg;i++)
    {
        dfs(graf[nod][i],lev+1);
        h[++k]=nod;
        l[k]=lev;
    }
}

void rmqq()
{
    for(int i=2;i<=k;i++)
        lg[i]=lg[i/2]+1;
    for(int i=1;i<=k;i++)
        rmq[0][i]=i;
    for(int i=1;(1<<i)<=k;i++)
    {
        for(int j=1;j<=k-(1<<i);j++)
        {
            rmq[i][j]=rmq[i-1][j+(1<<i-1)];
            if(l[rmq[i][j]]>l[rmq[i-1][j]])
                rmq[i][j]=rmq[i-1][j];
        }
    }
}

int lca(int a,int b)
{
    a=f[a];
    b=f[b];
    if(a>b)
        swap(a,b);
    int sol=rmq[lg[b-a+1]][b+1-(1<<lg[b-a+1])];
    if(l[sol]>l[rmq[lg[b-a+1]][a]])
        sol=rmq[lg[b-a+1]][a];
    return h[sol];
}

int main()
{
    int n,m,val,x,y;
    fin>>n>>m;
    for(int i=2;i<=n;i++)
    {
        fin>>val;
        graf[val].push_back(i);
    }
    dfs(1,0);
    rmqq();
    for(int i=1;i<=m;i++)
    {
        fin>>x>>y;
        fout<<lca(x,y)<<"\n";
    }
    return 0;
}