#include <bits/stdc++.h>
using namespace std;
//#define int long long
#define FOR(I, L, R) for(int I(L) ; I <= (int)R ; ++I)
#define FOD(I, R, L) for(int I(R) ; I >= (int)L ; --I)
#define FOA(I, A) for(auto &I : A)
#define print(A,L,R) FOR(OK, L, R){if(A[OK]<=-oo / 10||A[OK]>=oo)cout<<"- ";else cout<<A[OK]<<' ';}cout<<'\n';
#define prints(A) FOA(OK, A){cout<<OK<<' ';}cout << '\n';
#define printz(A,L,R) FOR(OK, 0, L){FOR(KO, 0, R){if(A[OK][KO]>-oo&&A[OK][KO]<oo)cout<<A[OK][KO]<<' ';else cout << "- ";} cout << '\n';}cout << '\n';
#define fs first
#define sd second
#define ii pair<int,int>
#define iii pair<int, ii>
#define all(A) A.begin(), A.end()
#define quickly ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
#define FILE "catinatree"
#define pow ladsf
const int N = 2e5 + 5;
const int SQRT = 465;
const int mod = 1e9 + 7;
const int oo = 1e9;
int n, k, limit, ans;
int dp[N][SQRT + 5], sz[N];
vector<int> g[N];
namespace LessSQRT{
static int f[N];
void DFS(int u, int par){
sz[u] = 1;
FOA(v, g[u]){
if(v == par){
continue;
}
DFS(v, u);
}
dp[u][0] = 1;
FOA(v, g[u]){
if(v == par){
continue;
}
FOR(i, 0, min(limit, sz[u])){
f[i] = dp[u][i];
}
FOR(i, 0, min(limit, sz[u])){
FOR(j, 0, min(limit, sz[v])){
if(i + j + 1 >= k){
dp[u][min(i, j + 1)] = max(dp[u][min(i, j + 1)], dp[v][j] + f[i]);
}
}
}
FOR(i, 0, min(limit, sz[v])){
dp[u][i + 1] = max(dp[u][i + 1], dp[v][i]);
}
FOD(i, min(limit, sz[u]), 0){
dp[u][i] = max(dp[u][i], dp[u][i + 1]);
}
sz[u] += sz[v];
}
FOD(i, min(limit, sz[u]), 0) ans = max(ans, dp[u][i]);
}
void solve(){
DFS(0, -1);
}
}
namespace MoreSQRT{
void DFS(int u, int par){
sz[u] = 1;
FOR(i, 0, limit) dp[u][i] = -oo;
dp[u][0] = oo;
dp[u][1] = 0;
FOA(v, g[u]){
if(v == par){
continue;
}
DFS(v, u);
FOD(i, min(sz[u], limit), 0){
FOR(j, 0, min(sz[v], limit)){
if(dp[u][i] + dp[v][j] + 1 >= k){
dp[u][i + j] = max(dp[u][i + j], min(dp[u][i], dp[v][j] + 1));
}
}
}
sz[u] += sz[v];
}
}
void solve(){
DFS(1, -1);
FOR(u, 0, n - 1){
FOD(i, limit, 0){
if(dp[u][i] >= 0){
ans = max(ans, i);
}
}
}
}
}
signed main(){ quickly
if(fopen(FILE".inp", "r")){
freopen(FILE".inp", "r", stdin);
freopen(FILE".out", "w", stdout);
}
cin >> n >> k;
limit = (n - 1) / k + 1;
++limit;
FOR(v, 1, n - 1){
int u;
cin >> u;
g[u].push_back(v);
g[v].push_back(u);
}
if(limit <= k){
MoreSQRT::solve();
}
else{
LessSQRT::solve();
}
cout << ans;
}
