Submission #854833

#	Time	Username	Problem	Language	Result	Execution time	Memory
854833		NeroZein	Papričice (COCI20_papricice)	C++17	0 / 110	1 ms	4956 KiB

papricice

#include "bits/stdc++.h"
using namespace std;

#ifdef Nero
#include "Deb.h"
#else
#define deb(...)
#endif

const int N = 2e5 + 5;

int sz[N]; 
vector<int> g[N]; 

void dfs(int v, int p) {
  sz[v] = 1;
  for (int u : g[v]) {
    if (u != p) {
      dfs(u, v);
      sz[v] += sz[u]; 
    }
  }
}

int dfs2(int v, int p, int n) {
  int next = 0;
  for (int u : g[v]) {
    if (u != p && sz[u] > sz[next]) {
      next = u;
    }
  }
  if (sz[v] > n / 3) {
    return dfs2(next, v, n); 
  }
  g[p].erase(find(g[p].begin(), g[p].end(), v)); 
  return v; 
}

int main(){
  ios::sync_with_stdio(false);
  cin.tie(nullptr);
  int n;
  cin >> n;
  for(int i = 0; i < n - 1; ++i) {
    int u, v;
    cin >> u >> v;
    g[u].push_back(v);
    g[v].push_back(u);
  }
  int max_size = 0;
  int min_size = n; 
  for (int rep = 0; rep < 2; ++rep) {
    dfs(1, 1); 
    int v = dfs2(1, 1, n); 
    max_size = max(max_size, sz[v]); 
    min_size = min(min_size, sz[v]);
    if (n != sz[1]) {
      max_size = max(max_size, sz[1] - sz[v]); 
      min_size = min(min_size, sz[1] - sz[v]); 
    }
  }
  cout << max_size - min_size << '\n'; 
  return 0;
}

• Subtask 1: 0 / 15
• Subtask 2: 0 / 35
• Subtask 3: 0 / 60