#include<stdio.h>
#include<vector>
using namespace std;
vector <int> g[100005];
int elr[200005],nvl[200005],i,n,k,x,m;
void dfs(int lvl, int nod)
{
	int N=g[nod].size();
	for(int i=0;i<N;i++)
	{
		elr[++k]=g[nod][i];
		nvl[k]=lvl;
		dfs(lvl+1,g[nod][i]);
		elr[++k]=g[nod][i];
		nvl[k]=lvl;
	}
}
int main()
{
	freopen("lca.in","r",stdin);
	freopen("lca.out","w",stdout);
	scanf("%d%d",&n,&m);
	for(i=2;i<=n;i++)
	{
		scanf("%d",&x);
		g[x].push_back(i);
	}
	dfs(1,1);
		
}