#include <bits/stdc++.h>
using namespace std;
#define all(x) (x).begin(), (x).end()
#define bg(x) (x).begin()
#define en(x) (x).end()
const int MAXN = 200'001, MAXLOG = 18;
int n, d;
vector<vector<int>> adj, up;
vector<int> depth, tin, tout;
int timer = 0;
map<int, set<int>> depth_map;
void dfs(int u, int p) {
tin[u] = timer++;
if (u == 0) depth[u] = 0;
else depth[u] = depth[p] + 1;
up[u][0] = p;
for (int i = 1; i < MAXLOG; i++) {
up[u][i] = up[up[u][i - 1]][i-1];
}
// depth_map[depth[u]].push_back(tin[u]);
depth_map[depth[u]].insert(u);
for (auto &v : adj[u]) {
if (v == p) continue;
dfs(v, u);
}
tout[u] = timer;
}
bool is_ancestor(int u, int v) {
return tin[u] <= tin[v] && tout[u] >= tout[v];
}
int find_lca(int u, int v) {
if (is_ancestor(u, v)) return u;
if (is_ancestor(v, u)) return v;
for (int i = MAXLOG - 1; i >= 0; i--) {
if (!is_ancestor(up[u][i], v)) {
u = up[u][i];
}
}
return up[u][0];
}
int dist(int u, int v) {
return depth[u] + depth[v] - 2 * depth[find_lca(u, v)];
}
// // how many nodes are there in the subtree of u at depth d
// int nodes_depth(int u, int dpth) {
// int upper =upper_bound(all(depth_map[dpth]), tout[u]) - bg(depth_map[dpth]);
// int lower = lower_bound(all(depth_map[dpth]), tin[u]) - bg(depth_map[dpth]);
// return upper - lower;
// }
void task1() { // n <= 18
int most = 0;
for (int mask = 0; mask < (1 << n); mask++) {
vector<int> active;
for (int bit = 0; bit < n; bit++) if (mask & (1 << bit)) active.push_back(bit);
bool valid = true;
for (auto &u : active) {
for (auto &v : active) {
if (u == v) continue;
valid = valid && dist(u, v) >= d;
}
}
if (valid) most = max(most, (int) active.size());
}
cout << most;
}
void remove_near(int u, int tim, vector<bool> &vis) {
if (tim > d) return;
vis[u] = true;
depth_map[depth[u]].erase(u);
for (auto &v : adj[u]) {
if (vis[v]) continue;
remove_near(v, tim+1, vis);
}
}
void task2() { // n <= 1500
int tl = 0;
int cur_depth = *max_element(all(depth));
vector<bool> vis(n, false);
while (cur_depth >= 0) {
if (depth_map[cur_depth].size() == 0) {
cur_depth--;
continue;
}
int cur_node = *depth_map[cur_depth].begin();
remove_near(cur_node, 0, vis);
tl++;
}
cout << tl;
}
void task3() { // n <= 2×10⁵
}
int main() {
cin.tie(0)->sync_with_stdio(0);
cin >> n >> d;
adj.assign(n, vector<int>());
for (int i = 1; i < n; i++) {
int xi; cin >> xi;
adj[i].push_back(xi);
adj[xi].push_back(i);
}
up.assign(n, vector<int>(MAXLOG, 0));
tin.assign(n, -1); tout.assign(n, -1); depth.assign(n, -1);
dfs(0, 0);
task2();
// if (n <= 18) task1();
// else if (n <= 1500) task2();
// else task3();
return 0;
}
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