#include <cstdio>
#include <algorithm>
#define N 100003
using namespace std;

struct graf
{
    int n;
    graf *next;
};

graf *g[N];
int rmq[20][2*N], h[2*N], l[2*N], first[N], lg[N*2];
int k;

void dfs(int x, int lvl)
{
    graf *p;
    h[++k]=x;
    l[k]=lvl;
    first[x]=k;
    for(p=g[x];p;p=p->next)
    {
        dfs(p->n, lvl+1);
        h[++k]=x;
        l[k]=lvl;
    }
}

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

int lca(int x, int y)
{
    int diff, ret;
    x=first[x];
    y=first[y];
    if(x>y) swap(x, y);
    diff=lg[y-x+1];
    if(l[rmq[diff][x]]>l[rmq[diff][y-(1<<diff)+1]])
    {
        ret=rmq[diff][y-(1<<diff)+1];
    }
    else
    {
        ret=rmq[diff][x];
    }
    return h[ret];
}

int main()
{
    freopen("lca.in", "r", stdin);
    freopen("lca.out", "w", stdout);
    int n, m, x, y, i;
    scanf("%d%d", &n, &m);
    for(i=2;i<=n;i++)
    {
        scanf("%d", &x);
        graf *p=new graf;
        p->n=i;
        p->next=g[x];
        g[x]=p;
    }
    dfs(1, 0);
    rmqb();
    while(m--)
    {
        scanf("%d%d", &x, &y);
        printf("%d\n", lca(x, y));
    }
}