#include <bits/stdc++.h>
#define maxn 100005
using namespace std;

int n,m,first[maxn<<1],l[maxn<<1],h[maxn<<1],k,lg[maxn<<1];
int rmq[20][maxn<<1];

vector <int >g[100005];
void citire()
{
    scanf("%d%d",&n,&m);
    int x;
    for (int i=2;i<=n;++i)
    {
        scanf("%d",&x);
        g[x].push_back(i);
    }
}
void dfs(int lev,int nod)
{
    h[++k]=nod;
    l[k]=lev;
    first[nod]=k;
    for (vector <int > :: iterator it=g[nod].begin();it!=g[nod].end();++it)
    {
        dfs(lev+1,*it);

        h[++k]=nod;
        l[k]=lev;
    }
}
void RMQ()
{
    for(int i = 2; i <= k; ++i)
        lg[i] = lg[i >> 1] + 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)
                {
                    int lx=1<<(i-1);
                    rmq[i][j]=rmq[i-1][j];
                    if (l[rmq[i][j]]>l[rmq[i-1][j+lx]])
                        rmq[i][j]=rmq[i-1][j+lx];
                }
}
int lca(int f1,int f2)
{
    int a,b;
    a=first[f1];
    b=first[f2];
    if (a>b)
        swap(a,b);
    int dif=b-a+1,ras;
    int lgx=lg[dif];
    int sol=rmq[lgx][a];
    dif=dif-(1<<lgx);
    if (dif && l[rmq[lgx][a+dif]]<l[sol])
        sol=rmq[lgx][a+dif];
    return h[sol];
}
int main()
{
    freopen("lca.in","r",stdin);
    freopen("lca.out","w",stdout);
    citire();
    dfs(0,1);
    RMQ();
    for (int i=1;i<=m;++i)
    {
        int x,y;
        scanf("%d%d",&x,&y);
        printf("%d\n",lca(x,y));
    }
    return 0;
}