#include <bits/stdc++.h>
using namespace std;

/// lowest common ancestor
int n,s;
const int NMAX=100000;
int parent[NMAX+5],sqparent[NMAX+5],depth[NMAX+5];
int depth_max=0;
int h;
vector<int>v[NMAX+5];
void dfs(int nod)
{
    if(depth[nod]>depth_max)depth_max=depth[nod];
    vector<int>::iterator it;
    for(it=v[nod].begin();it!=v[nod].end();it++)
    {
        depth[*it]=depth[nod]+1;
        dfs(*it);
    }
}
void dfs1(int nod)
{
    vector<int>::iterator it;
    for(it=v[nod].begin();it!=v[nod].end();it++)
    {
        depth[*it]=depth[nod]+1;
        if(depth[*it]%h==0)sqparent[*it]=nod;
        else
            sqparent[*it]=sqparent[nod];
        dfs1(*it);
    }
}
int naivelca(int u ,int v)
{
    if(depth[u]>depth[v])swap(u,v);
    if(depth[u]==depth[v])
    {
        if(u==v)return u;
        u=parent[u];
        v=parent[v];
        return naivelca(u,v);
    }
    v=parent[v];
    return naivelca(u,v);
}
int sqlca(int u,int v)
{
    if(depth[u]>depth[v])swap(u,v);
    if(sqparent[u]!=sqparent[v])
    {
         return sqlca(u,sqparent[v]);
    }
    return naivelca(u,v);
}

int main()
{
    freopen("lca.in","r",stdin);
    freopen("lca.out","w",stdout);
    int m,n,i,j;
    scanf("%d%d",&m,&n);
    for(i=2;i<=m;i++)
        {scanf("%d",&parent[i]);v[parent[i]].push_back(i);}
        dfs(1);
        parent[1]=0;
        depth[0]=-1;
    h=(int)sqrt((double)depth_max);
    fill(depth,depth+NMAX,0);
    dfs1(1);
    for(i=1;i<=n;i++)
    {
        int x,y;
        scanf("%d%d",&x,&y);
        int ans=sqlca(x,y);
        printf("%d\n",ans);
    }
    return 0;
}