Submission #1256258

#	Time	Username	Problem	Language	Result	Execution time	Memory
1256258		bynix	Obstacles for a Llama (IOI25_obstacles)	C++20	23 / 100	84 ms	9032 KiB

obstacles

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

vector<int> id;

int find(int x){
  return x == id[x] ? x : find(id[x]);
}

void unite(int a, int b){
  a = find(a), b = find(b);
  if (a > b) swap(a, b);
  id[b] = a;
}

void initialize(vector<int> T, vector<int> H) {
  int N = T.size(), M = H.size();
  
  id.resize(3*M, 0);
  for (int i = 0; i < 3*M; i++) id[i] = i;

  if ((T[0] > H[0]) == (T[1] > H[0])) unite(0, M);
  if ((T[1] > H[0]) == (T[2] > H[0])) unite(M, 2*M);

  for (int i = 1; i < M; i++){
    if ((T[0] > H[i]) == (T[0] > H[i-1])) unite(i-1, i);
    
    if ((T[0] > H[i]) == (T[1] > H[i])) unite(i, i + M);
    if ((T[1] > H[i]) == (T[1] > H[i-1])) unite(i-1 + M, i + M);
    
    if ((T[1] > H[i]) == (T[2] > H[i])) unite(i+M, i + 2*M);
    if ((T[2] > H[i]) == (T[2] > H[i-1])) unite(i-1 + 2*M, i + 2*M);
  }
}

bool can_reach(int L, int R, int S, int D) {
  return find(S) == find(D);
}

• Subtask 0: 0 / 0
• Subtask 1: 10 / 10
• Subtask 2: 0 / 14
• Subtask 3: 13 / 13
• Subtask 4: 0 / 21
• Subtask 5: 0 / 25
• Subtask 6: 0 / 17