Submission #293424

#	Time	Username	Problem	Language	Result	Execution time	Memory
293424		rama_pang	Painting Walls (APIO20_paint)	C++14	100 / 100	974 ms	13816 KiB

paint

#include "paint.h"
#include <bits/stdc++.h>
using namespace std;

int minimumInstructions(int N, int M, int K, vector<int> C, vector<int> A, vector<vector<int>> B) {
  vector<vector<int>> colors(K);
  for (int i = 0; i < M; i++) {
    for (auto c : B[i]) {
      colors[c].emplace_back(i);
    }
  }

  int mx = 0;
  vector<bool> possible(N + 1, false);
  auto Update = [&](int i, int sgn) {
    static vector<int> freq(M, 0);
    static vector<int> cnt(M + 1, 0);
    auto UpdateMax = [&]() {
      while (mx + 1 <= M && cnt[mx + 1] > 0) mx++;
      while (mx > 0 && cnt[mx] == 0) mx--;
    };
    for (auto j : colors[C[i]]) {
      int v = j - (i % M);
      if (v < 0) v += M;
      if (sgn == 1) {
        freq[v] += sgn;
        cnt[freq[v]] += sgn;
      } else if (sgn == -1) {
        cnt[freq[v]] += sgn;
        freq[v] += sgn;
      }
      UpdateMax();
    }
  };

  for (int i = 0; i < M; i++) {
    Update(i, +1);
  }
  if (mx == M) {
    possible[0] = true;
  }
  for (int i = 0; i + M < N; i++) {
    Update(i, -1);
    Update(i + M, +1);
    if (mx == M) {
      possible[i + 1] = true;
    }
  }

  deque<pair<int, int>> q;
  vector<int> dist(N + 1, -1);
  q.emplace_front(0, 0);
  dist[0] = 0;
  while (!q.empty()) {
    int u = q.front().first;
    int d = q.front().second;
    q.pop_front();
    if (dist[u] != d) {
      continue;
    }
    if (possible[u] && (dist[u + M] == -1 || dist[u + M] > dist[u] + 1)) {
      dist[u + M] = dist[u] + 1;
      q.emplace_back(u + M, dist[u + M]);
    }
    if (u > 0 && (dist[u - 1] == -1 || dist[u - 1] > dist[u])) {
      dist[u - 1] = dist[u];
      q.emplace_front(u - 1, dist[u - 1]);
    }
  }
  return dist[N];
}

• Subtask 1: 12 / 12
• Subtask 2: 15 / 15
• Subtask 3: 13 / 13
• Subtask 4: 23 / 23
• Subtask 5: 37 / 37