#include <bits/stdc++.h>
#include <iostream>
#include <vector>
#include <set>
using namespace std;
#define el endl
#define dl double
#define ll long long
#define faster ios_base::sync_with_stdio(false); cin.tie(0); cout.tie(0);
#define op 1005
#define _c const int
_c N = op;
vector <int>adj[N];
int a[N][N];
int k,n;
int cnt = 0;
int dfs(int u){
	int tmp_dinh = 1;
	for(int v:adj[u]){
		tmp_dinh+=dfs(v);
	}
	if(tmp_dinh >= k){
		cnt++;
		return 0;
	}
	return tmp_dinh;
}
void inp(){
	cin >> k >> n;
	for(int i = 2; i <= n; i++){
		int x; cin >> x;
		adj[x].push_back(i);
	}
	dfs(1);
	cout << cnt;
}
int main(){
	inp();
	faster;
	return 0;
}