/*
#include <cstdio>
using namespace std;
int n,tata[100001],a[20][100001],niv[100001],m,p;
void dfs(int x,int lev)
{
    if(tata[x]){if(niv[tata[x]]){niv[x]=niv[tata[x]]+lev;return;}dfs(tata[x],lev+1);}
}
int query(int r,int q, int p)
{
    int i,j,c;
    if(niv[r]<niv[q]){c=r;r=q;q=c;}
    for(j=p;j>=0;j--)
        if(a[j][r]&&niv[a[j][r]]>=niv[q])
            {r=a[j][r];if(niv[r]==niv[q])break;}
            else if(niv[r]==niv[q])break;
        for(j=p;j>=0;j--)
        {
        if(a[j][r]&&a[j][r]!=a[j][q]){r=a[j][r];q=a[j][q];}
        }
        if(r==q)return r;
return tata[r];
}
int main()
{
    int i,j,k,p,r;
    freopen("lca.in","r",stdin);
    freopen("lca.out","w",stdout);
    scanf("%d%d",&n,&m);
    for(i=2; i<=n; i++)
    {
        scanf("%d",&p );
        tata[i]=a[0][i]=p;
    }
    tata[1]=a[0][1]=0;
    niv[1]=1;
    for(i=2;i<=n;i++)
        dfs(i,1);
       k=n;p=-1;
       while(k){p++;k/=2;}
        for(j=1;j<=p;j++)
            for(i=1;i<=n;i++)
            if(a[j-1][i])a[j][i]=a[j-1][a[j-1][i]];
        for(i=0;i<m;i++)
        {
            scanf("%d%d",&r,&k);

            int rasp=query(r,k,p);
            printf("%d\n",rasp);
        }

    return 0;
}

VARIANTA STRAMOSHEASCA :))
*/


#include <cstdio>
#include <vector>
#include <stdlib.h>
using namespace std;


int n,niv[100001],eul[200003],k,loga[200003],r[20][200003],pos[100001];
vector<int>tata[100002];
void parc(int x,int l)
{
int a=tata[x].size(),i;
eul[++k]=x;niv[x]=l;
   for(i=0;i<a;i++)
   {
       parc(tata[x][i],l+1);
       eul[++k]=x;
   }
}
int mi(int a,int b)
{
    if(niv[a]>niv[b])return b;
        return a;
}
int main()
{int i,j,q,p,b,t,m,f;
freopen("lca.in","r",stdin);
freopen("lca.out","w",stdout);
scanf("%d%d",&n,&m);
    for(i=2;i<=n;i++)
    {
        scanf("%d",&b);
        tata[b].push_back(i); //pun nodurile care-l au ca tata pe b
    }
parc(1,0);
loga[1]=0;
for(i=2;i<=2*n;i++)
    loga[i]=loga[i/2]+1;
    for(i=1;i<=2*n;i++)
        {r[0][i]=eul[i];
        if(pos[eul[i]]==0)pos[eul[i]]=i ;
        }



    for(j=1;j<=loga[2*n];j++)
    {b=1<<j;
        for(i=b;i<=2*n;i++)
        {
            r[j][i]=mi(r[j-1][i],r[j-1][i-b/2]);
        }
    }

    for(i=0;i<m;i++)
    {
        scanf("%d%d",&q,&p);


        if(pos[p]>pos[q]){t=p;p=q;q=t;}
        t=loga[pos[q]-pos[p]+1];
        f=mi(r[t][pos[q]],r[t][pos[p]+(1<<t)-1]);
        printf("%d\n",f);

    }



    return 0;
}