Submission #1067643

#	Time	Username	Problem	Language	Result	Execution time	Memory
1067643		MilosMilutinovic	Make them Meet (EGOI24_makethemmeet)	C++14	10 / 100	1 ms	348 KiB

Main

#include <bits/stdc++.h>

using namespace std;

int main() {
  ios::sync_with_stdio(false);
  cin.tie(0);
  int n, m;
  cin >> n >> m;
  vector<vector<int>> g(n);
  for (int i = 0; i < m; i++) {
    int u, v;
    cin >> u >> v;
    g[u].push_back(v);
    g[v].push_back(u);
  }
  auto Subtask1 = [&]() {
    return m == n - 1 && (int) g[0].size() == n - 1;
  };
  auto Subtask2 = [&]() {
    return m == n * (n - 1) / 2;
  };
  auto Subtask3 = [&]() {
    bool ok = (m == n - 1);
    for (int i = 0; i < n; i++) {
      for (int j : g[i]) {
        if (abs(i - j) > 1) {
          ok = false;
        }
      }
    }
    return ok;
  };
  auto Tree = [&]() {
    return m == n - 1;
  };
  if (Subtask1()) {
    // Subtask 1
    cout << 2 * (n - 1) + 1 << '\n';
    for (int i = 0; i < n; i++) {
      cout << 1 << " ";
    }
    cout << '\n';
    for (int i = 1; i < n; i++) {
      for (int j = 0; j < n; j++) {
        if (j == 0 || j == i) {
          cout << 1 << " ";
        } else {
          cout << 2 << " ";
        }
      }
      cout << '\n';
      for (int j = 0; j < n; j++) {
        if (j == 0 || j == i) {
          cout << 1 << " ";
        } else {
          cout << 2 << " ";
        }
      }
      cout << '\n';
    }
    return 0;
  }
  /* if (Subtask3()) {
    cout << (n - 1) * (n - 1) << '\n';
    for (int i = 0; i + 1 < n; i++) {
      for (int j = 0; j + 1 < n; j++) {
        int col = 2;
        for (int k = 0; k < n; k++) {
          if (k == j || k == j + 1) {
            cout << 1 << " ";
          } else {
            cout << col << " ";
            col += 1;
          }
        }
        cout << '\n';
      }
    }
    return 0;
  } */
  if (Tree()) {
    vector<vector<int>> res;
    auto Do = [&](vector<int> v) {
      vector<int> seq(n, -1);
      for (int i : v) {
        seq[i] = 1;
      }
      int col = 2;
      for (int i = 0; i < n; i++) {
        if (seq[i] == -1) {
          seq[i] = col++;
        }
      }
      res.push_back(seq);
    };
    vector<bool> del(n);
    vector<int> sz(n);
    function<void(int, int)> DfsSz = [&](int v, int pv) {
      sz[v] = 1;
      for (int u : g[v]) {
        if (u == pv || del[u]) {
          continue;
        }
        DfsSz(u, v);
        sz[v] += sz[u];
      }
    };
    function<int(int, int, int)> FindCentroid = [&](int v, int pv, int n) {
      for (int u : g[v]) {
        if (u == pv || del[u] || sz[u] * 2 < n) {
          continue;
        }
        return FindCentroid(u, v, n);
      }
      return v;
    };
    function<void(int, int)> Dfs = [&](int v, int pv) {
      for (int u : g[v]) {
        if (u == pv || del[u]) {
          continue;
        }
        Do({u, v});
        Dfs(u, v);
      }
      if (v != pv) {
        Do({v, pv});
      }
    };
    function<void(int)> Solve = [&](int v) {
      DfsSz(v, v);
      v = FindCentroid(v, v, sz[v]);
      del[v] = true;
      Dfs(v, v);
      for (int u : g[v]) {
        if (!del[u]) {
          Solve(u);
        }
      }
    };
    Solve(0);
    cout << (int) res.size() << '\n';
    for (auto& c : res) {
      for (int i = 0; i < n; i++) {
        cout << c[i] << " ";
      }
      cout << '\n';
    }
  }
  return 0;
}

Compilation message (stderr)

Main.cpp: In function 'int main()':
Main.cpp:20:8: warning: variable 'Subtask2' set but not used [-Wunused-but-set-variable]
   20 |   auto Subtask2 = [&]() {
      |        ^~~~~~~~
Main.cpp:23:8: warning: variable 'Subtask3' set but not used [-Wunused-but-set-variable]
   23 |   auto Subtask3 = [&]() {
      |        ^~~~~~~~

• Subtask 1: 10 / 10
• Subtask 2: 0 / 13
• Subtask 3: 0 / 11
• Subtask 4: 0 / 36
• Subtask 5: 0 / 30