Submission #204383

#	Time	Username	Problem	Language	Result	Execution time	Memory
204383		ADJA	Split the Attractions (IOI19_split)	C++14	29 / 100	603 ms	1048580 KiB

split

#include "split.h"
 
#include <iostream>
#include <cstdio>
#include <cstdlib>
#include <vector>
#include <set>
#include <map>
#include <algorithm>
#include <bitset>
#include <cmath>
#include <queue>
#include <stack>
#include <string>
 
#define sz(x) (int) x.size()
#define all(x) x.begin(), x.end()
 
using namespace std;
 
const int MAXN = 105000;
 
int n, a, b, c;
vector <pair<int, int>> p;
vector<int> g[MAXN];
vector<int> res;
int sz[MAXN];
int par[MAXN];
int deg[MAXN];
bool used[MAXN];
 
void dfs(int v, int p = -1) {
  sz[v] = 1;
  par[v] = p;
  for (int to : g[v]) {
    if (to == p) {
      continue;
    }
    dfs(to, v);
    sz[v] += sz[to];
  }
}
 
void paint(int v, int bad, int color, int& need) {
  // cerr << v << " " << color << " " << need << endl;
  if (v == bad || need == 0) {
    return;
  }
  res[v] = color;
  need--;
  for (int to : g[v]) {
    if (to == par[v]) {
      continue;
    }
    paint(to, bad, color, need);
  }
}

void doPaint(int v, int num) {
  used[v] = true;
  if (num <= a) {
    res[v] = 1;
  } else if (num <= a + b) {
    res[v] = 2;
  } else {
    res[v] = 3;
  }
  for (int to : g[v]) {
    if (used[to]) {
      continue;
    }
    doPaint(to, num + 1);
  }
}

void solveOne() {
  int st = 0;
  for (int i = 0; i < n; i++) {
    if (deg[i] == 1) {
      st = i;
    }
  }
  doPaint(st, 1);
}
 
vector<int> find_split(int N, int A, int B, int C, vector<int> FROM, vector<int> TO) {
  n = N; a = A; b = B; c = C;
  p = {{a, 1}, {b, 2}, {c, 3}};  
  res.assign(n, 0);
  sort(all(p));
 
  for (int i = 0; i < sz(FROM); i++) {
    int from = FROM[i], to = TO[i];
    g[from].push_back(to);
    g[to].push_back(from);
    deg[from]++; deg[to]++;
  }
  int mxDeg = deg[0];
  for (int i = 0; i < n; i++) {
    mxDeg = max(mxDeg, deg[i]);
  }
  if (mxDeg == 2) {
    solveOne();
    return res;
  }
 
  dfs(0);
  /* for (int i = 0; i < n; i++) {
    cerr << sz[i] << " ";
  }
  cerr << endl; */
 
  do {
    for (int i = 0; i < n; i++) {
      // cerr << sz[i] << " " << n - sz[i] << " " << p[0].first << " " << p[1].first << endl;
      if (sz[i] >= p[0].first && n - sz[i] >= p[1].first) {
        res.assign(n, p[2].second);
        paint(0, i, p[1].second, p[1].first);
        paint(i, -1, p[0].second, p[0].first);
        return res;
      }
    }
  } while (next_permutation(all(p)));
 
  return res;
}

• Subtask 1: 7 / 7
• Subtask 2: 0 / 11
• Subtask 3: 22 / 22
• Subtask 4: 0 / 24
• Subtask 5: 0 / 36