Submission #496537

#	Time	Username	Problem	Language	Result	Execution time	Memory
496537		600Mihnea	Cats or Dogs (JOI18_catdog)	C++17	38 / 100	3070 ms	7156 KiB

catdog

#include "catdog.h"
#include <bits/stdc++.h>

using namespace std;


const int N = (int) 1e5 + 7;
const int INF = (int) 1e9 + 7;
int n;
int no_cat[N];
int no_dog[N];
vector<int> g[N];
int type[N];

/**

nothing = 0
cat = 1
dog = 2

**/

void dfs(int a, int p = -1) {
  if (type[a] == 0) {
    no_cat[a] = no_dog[a] = 0;
    for (auto &b : g[a]) {
      if (b == p) {
        continue;
      }
      dfs(b, a);
      no_cat[a] += min(no_cat[b], 1 + no_dog[b]);
      no_dog[a] += min(no_dog[b], 1 + no_cat[b]);
    }
    return;
  }
  if (type[a] == 1) {
    no_cat[a] = INF;
    no_dog[a] = 0;
    for (auto &b : g[a]) {
      if (b == p) {
        continue;
      }
      dfs(b, a);
      no_dog[a] += min(no_dog[b], 1 + no_cat[b]);
    }
    return;
  }
  if (type[a] == 2) {
    no_cat[a] = 0;
    no_dog[a] = INF;
    for (auto &b : g[a]) {
      if (b == p) {
        continue;
      }
      dfs(b, a);
      no_cat[a] += min(no_cat[b], 1 + no_dog[b]);
    }
    return;
  }
  assert(false);
}

void initialize(int nn, std::vector<int> edgesA, std::vector<int> edgesB) {
  n = nn;
  for (int i = 0; i < n - 1; i++) {
    int a = edgesA[i];
    int b = edgesB[i];
    g[a].push_back(b);
    g[b].push_back(a);
  }


}

int cat(int v) {
  type[v] = 1;
  dfs(1);
  return min(no_cat[1], no_dog[1]);
}

int dog(int v) {
  type[v] = 2;
  dfs(1);
  return min(no_cat[1], no_dog[1]);
}

int neighbor(int v) {
  type[v] = 0;
  dfs(1);
  return min(no_cat[1], no_dog[1]);
}

• Subtask 1: 8 / 8
• Subtask 2: 30 / 30
• Subtask 3: 0 / 62