Submission #902435

#	Time	Username	Problem	Language	Result	Execution time	Memory
902435		nguyentunglam	Painting Walls (APIO20_paint)	C++17	100 / 100	360 ms	18676 KiB

paint

#include<bits/stdc++.h>
#define fi first
#define se second
#define endl "\n"
#define ii pair<int, int>
using namespace std;

const int N = 2e5 + 10;

bool good[N];

int n, m, k;

int f[N], g[N], bit[N], dp[N];

vector<int> color[N];

void add(int pos, int val) {
  while (pos <= n) {
    bit[pos] = min(bit[pos], val);
    pos += pos & -pos;
  }
}

int get(int pos) {
  int ret = 1e9;
  while (pos) {
    ret = min(ret, bit[pos]);
    pos -= pos & -pos;
  }
  return ret;
}

int minimumInstructions(int N, int M, int K, std::vector<int> c, std::vector<int> a, std::vector<std::vector<int>> b) {
  n = N; m = M; k = K;
  for(int i = 0; i < m; i++) {
    for(int &j : b[i]) {
      color[j].push_back(i);
    }
  }
  for(int i = n - 1; i >= 0; i--) {
    for(int &j : color[c[i]]) {
      f[j] = g[(j + 1) % m] + 1;
      if (f[j] >= m) good[i] = 1;
    }
    if (i + 1 < n) for(int &j : color[c[i + 1]]) g[j] = 0;
    for(int &j : color[c[i]]) {
      g[j] = f[j];
      f[j] = 0;
    }
  }

  for(int i = 0; i < n; i++) dp[i] = bit[i] = 1e9;

  if (!good[n - m]) return -1;

  dp[n - m] = 1;

  if (n - m) add(n - m, 1);

  for(int i = n - m - 1; i >= 0; i--) if (good[i]) {
    dp[i] = get(i + m) + 1;
    if (i) add(i, dp[i]);
  }

  if (dp[0] > 1e8) return -1;

  return dp[0];
}

#ifdef ngu
int main() {

  freopen ("task.inp", "r", stdin);
  freopen ("task.out", "w", stdout);

  int n, m, k;
  cin >> n >> m >> k;

  vector<int> c(n), a(m);

  vector<vector<int> > b;

  for(int i = 0; i < n; i++) cin >> c[i];

//  for(int i = 0; i < n; i++) cout << c[i] << " "; cout << endl;

  for(int i = 0; i < m; i++) {
    cin >> a[i];
    vector<int> tmp(a[i]);
    for(int j = 0; j < a[i]; j++) cin >> tmp[j];
    b.push_back(tmp);
  }
  cout << minimumInstructions(n, m, k, c, a, b);
}
#endif // ngu

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