Submission #752149

#	Time	Username	Problem	Language	Result	Execution time	Memory
752149		Sam_a17	Meetings 2 (JOI21_meetings2)	C++17	100 / 100	2578 ms	41404 KiB

meetings2

#define _CRT_SECURE_NO_WARNINGS
#include <bits/stdc++.h>
//#include "temp.cpp"
#include <cstdio>
using namespace std;
 
#ifndef ONLINE_JUDGE
#define dbg(x) cerr << #x <<" "; print(x); cerr << endl;
#else
#define dbg(x)
#endif
 
#define sz(x) (int((x).size()))
#define len(x) (int)x.length()
#define all(x) (x).begin(), (x).end()
#define rall(x) (x).rbegin(), (x).rend()
#define clr(x) (x).clear()
#define blt(x) __builtin_popcount(x)
#define uniq(x) x.resize(unique(all(x)) - x.begin());
 
#define pb push_back
#define popf pop_front
#define popb pop_back
#define ld long double
#define ll long long
 
void print(long long t) {cerr << t;}
void print(int t) {cerr << t;}
void print(string t) {cerr << t;}
void print(char t) {cerr << t;}
void print(double t) {cerr << t;}
void print(unsigned long long t) {cerr << t;}
void print(long double t) {cerr << t;}
 
template <class T, class V> void print(pair <T, V> p);
template <class T> void print(vector <T> v);
template <class T> void print(set <T> v);
template <class T, class V> void print(map <T, V> v);
template <class T> void print(multiset <T> v);
template <class T> void print(T v[],T n) {cerr << "["; for(int i = 0; i < n; i++) {cerr << v[i] << " ";} cerr << "]";}
template <class T, class V> void print(pair <T, V> p) {cerr << "{"; print(p.first); cerr << ","; print(p.second); cerr << "}";}
template <class T> void print(vector <T> v) {cerr << "[ "; for (T i : v) {print(i); cerr << " ";} cerr << "]";}
template <class T> void print(deque <T> v) {cerr << "[ "; for (T i : v) {print(i); cerr << " ";} cerr << "]";}
template <class T> void print(set <T> v) {cerr << "[ "; for (T i : v) {print(i); cerr << " ";} cerr << "]";}
template <class T> void print(multiset <T> v) {cerr << "[ "; for (T i : v) {print(i); cerr << " ";} cerr << "]";}
template <class T, class V> void print(map <T, V> v) {cerr << "[ "; for (auto i : v) {print(i); cerr << " ";} cerr << "]";}
 
#include <ext/pb_ds/assoc_container.hpp>
using namespace __gnu_pbds;
#define nl '\n'

// for random generations
mt19937 myrand(chrono::steady_clock::now().time_since_epoch().count());
// mt19937 myrand(131);

// for grid problems
int dx[8] = {-1,0,1,0,1,-1,1,-1};
int dy[8] = {0,1,0,-1,1,1,-1,-1};
 
// lowest / (1 << 17) >= 1e5 / (1 << 18) >= 2e5 / (1 << 21) >= 1e6
void fastIO() {
  ios_base::sync_with_stdio(false);
  cin.tie(nullptr); cout.tie(nullptr);
}
// file in/out
void setIO(string str = "") {
  fastIO();
 
  if (str != "") {
    freopen((str + ".in").c_str(), "r", stdin);
    freopen((str + ".out").c_str(), "w", stdout);
  } else {
    // freopen("input.txt", "r", stdin);
    // freopen("output.txt", "w", stdout);
  }
}
 
// Indexed Set
template <class T> using Tree = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
const int N = 2e5 + 10, LOG = 21;
vector<int> adj[N];
bool used[N];
int n, sz[N], most;
int compSize;

struct segTreeMax {
  vector<long long> mTree;
  int size;
 
  void init(long long n) {
    size = 1;
    while(size < n)  {
      size *= 2;
    }
    mTree.assign(2 * size - 1, -1);
  }
 
  void upd(int u, long long v, int x, int lx, int rx) { // set value at pos u
    if(rx - lx == 1) {
      if(v == -1) {
        mTree[x] = -1;
      } else {
        mTree[x] = max(mTree[x], v);
      }
      return;
    }
 
    int m = (lx + rx) / 2;
    if(u < m) {
      upd(u, v, 2 * x + 1, lx, m);
    }else {
      upd(u, v, 2 * x + 2, m, rx);
    }
    mTree[x] = max(mTree[2 * x + 1], mTree[2 * x + 2]);
  }
 
  void upd(int u, long long v) {
    upd(u, v, 0, 0, size);
  }
 
  long long qry (int l, int r, int x, int lx, int rx) { // range queries
    if(l >= rx || lx >= r) {
      return -1;
    }
    if(lx >= l && r >= rx) {
      return mTree[x];
    }
 
    int m = (rx + lx) / 2;
    long long s1 = qry(l, r, 2 * x + 1, lx, m);
    long long s2 = qry(l, r, 2 * x + 2, m, rx);
    return max(s1, s2);
  }
 
  long long qry(int l, int r) {
    return qry(l, r, 0, 0, size);
  }
};

segTreeMax seg_max;

void dfs_sz(int node, int parent) {
  sz[node] = 1, compSize++;
  for(auto i: adj[node]) {
    if(i == parent || used[i]) continue;
    dfs_sz(i, node);
    sz[node] += sz[i];
  }
}

int get_centroid(int node, int parent) {
  for(auto i: adj[node]) {
    if(i == parent || used[i]) continue;
    if(2 * sz[i] > compSize) {
      return get_centroid(i, node);
    }
  }
  return node;
}

int centroid(int u) {
  compSize = 0;
  dfs_sz(u, 0);

  int p = get_centroid(u, 0);
  if(!most) most = p;
  dfs_sz(p, 0);
  return p;
}


bool use[N];
vector<pair<int, int>> curr;
vector<int> full;
int ans[N], bb;

void solve(int node, int parent, int depth, int lim) {
  if(depth) {
    if(!use[sz[node]]) {
      full.push_back(sz[node]);
      use[sz[node]] = true;
    }

    curr.push_back({sz[node], depth});

    ans[2 * min(sz[node], lim)] = max(ans[2 * min(sz[node], lim)], depth);
  }

  for(auto i: adj[node]) {
    if(i == parent || used[i]) continue;
    if(!depth) {
      solve(i, node, depth + 1, n - sz[i]);
    } else {
      solve(i, node, depth + 1, lim);
    }

    if(parent) continue;

    for(auto j: curr) {
      int max_dep = seg_max.qry(j.first, n + 1);

      if(max_dep != -1) {
        ans[j.first * 2] = max(ans[j.first * 2], max_dep + j.second); 
      }
    }

    for(auto j: curr) {
      seg_max.upd(j.first, j.second);
    }

    curr.clear();
  }
}

void centroid_decomposition() {
  queue<int> q;
  q.push(1);

  while(!q.empty()) {
    auto u = q.front();
    q.pop();

    int get = centroid(u);
    solve(get, 0, 0, 0);

    for(auto i: full) {
      use[i] = false;
      seg_max.upd(i, -1);
    }
    full.clear();

    reverse(all(adj[get]));

    solve(get, 0, 0, 0);
    
    for(auto i: full) {
      use[i] = false;
      seg_max.upd(i, -1);
    }
    full.clear();

    used[get] = true;
    for(auto i: adj[get]) {
      if(used[i] || sz[i] == 1) continue;
      q.push(i);
    }
  }
}

void solve_() {
  cin >> n;

  seg_max.init(n + 5);
  for(int i = 1; i <= n - 1; i++) {
    int a, b; cin >> a >> b;
    adj[a].push_back(b);
    adj[b].push_back(a);
  }

  centroid_decomposition();

  for(int i = n; i >= 1; i--) {
    ans[i] = max(ans[i], ans[i + 1]);
  }

  for(int i = 1; i <= n; i++) {
    if(i & 1) {
      cout << 1 << '\n';
    } else {
      cout << ans[i] + 1 << '\n';
    }
  }
}


int main() {
  setIO();
  
  auto solve = [&](int test_case)-> void {
    while(test_case--) {
      solve_();
    }
  };
 
  int test_cases = 1; 
  // cin >> test_cases;
  solve(test_cases);
 
  return 0;
}

Compilation message (stderr)

meetings2.cpp: In function 'void setIO(std::string)':
meetings2.cpp:70:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   70 |     freopen((str + ".in").c_str(), "r", stdin);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
meetings2.cpp:71:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   71 |     freopen((str + ".out").c_str(), "w", stdout);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 4 / 4
• Subtask 2: 16 / 16
• Subtask 3: 80 / 80