oj.uz

Submission #1043794

# Submission time Handle Problem Language Result Execution time Memory
1043794 2024-08-04T18:10:47 Z Hydrolyzed Nafta (COI15_nafta) C++14
100 / 100
 208 ms 157336 KB 
#include <bits/stdc++.h>

using namespace std;
using ll = long long;

const int MxN = 2020;
const int INF = 1e9 + 100;
const int di[] = {0, -1, 1, 0};
const int dj[] = {-1, 0, 0, 1};

char s[MxN][MxN];
bool visited[MxN][MxN];
pair<int, int> border;
int n, m, sum, v[MxN], w[MxN][MxN], x[MxN][MxN], mem[MxN][MxN], cost[MxN][MxN];
vector<pair<int, int>> to_add[MxN];
vector<int> to_remove[MxN];

void dfs(int i, int j) {
  visited[i][j] = true;
  border = make_pair(min(border.first, j), max(border.second, j));
  sum += (s[i][j] - '0');
  for(int k=0; k<4; ++k) {
    int ii = i + di[k];
    int jj = j + dj[k];
    if(ii < 1 || jj < 1 || ii > n || jj > m) {
      continue;
    }
    if(visited[ii][jj] || s[ii][jj] == '.') {
      continue;
    }
    dfs(ii, jj);
  }
}

inline int get_cost(int l, int r) {
  return v[r] - x[l][r];
}

void divide(int l, int r, int opt_l, int opt_r, vector<int> &dp, vector<int> &new_dp) {
  if(l > r) {
    return ;
  }
  int mid = (l + r) >> 1;
  pair<int, int> best = make_pair(-INF, -1);
  for(int k=opt_l; k<=min(opt_r, mid); ++k) {
    best = max(best, make_pair(dp[k] + get_cost(k, mid), k));
  }
  new_dp[mid] = best.first;
  divide(l, mid - 1, opt_l, best.second, dp, new_dp);
  divide(mid + 1, r, best.second, opt_r, dp, new_dp);
}

signed main(int argc, char *argv[]) {
  cin.tie(nullptr)->ios::sync_with_stdio(false);
  cin >> n >> m;
  for(int i=1; i<=n; ++i) {
    cin >> (s[i] + 1);
  }
  for(int i=1; i<=n; ++i) {
    for(int j=1; j<=m; ++j) {
      if(s[i][j] == '.' || visited[i][j]) {
        continue;
      }
      sum = 0;
      border = make_pair(j, j);
      dfs(i, j);
      mem[border.first][border.second] += sum;
    }
  }
  for(int i=1; i<=m; ++i) {
    for(int j=i; j<=m; ++j) {
      v[i] += mem[i][j];
      v[j + 1] -= mem[i][j];
    }
  }
  for(int i=1; i<=m; ++i) {
    for(int j=m; j>=1; --j) {
      w[i][j] = w[i][j + 1]  + mem[i][j];
    }
  }
  for(int i=1; i<=m; ++i) {
    for(int j=m; j>=1; --j) {
      x[i][j] = x[i - 1][j] + w[i][j];
    }
  }
  for(int i=1; i<=m; ++i) {
    v[i] += v[i - 1];
  }
  vector<int> dp(m + 1, -INF), new_dp(m + 1, -INF);
  for(int i=1; i<=m; ++i) {
    dp[i] = v[i];
  }
  cout << *max_element(dp.begin(), dp.end()) << "\n";
  for(int c=2; c<=m; ++c) {
    divide(1, m, 1, m, dp, new_dp);
    dp = new_dp;
    cout << *max_element(dp.begin(), dp.end()) << "\n";
  }
  return 0;
}

Subtask #1
11.0 / 11.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 7004 KB Output is correct
2 Correct 1 ms 7004 KB Output is correct
3 Correct 1 ms 7004 KB Output is correct
4 Correct 1 ms 7004 KB Output is correct
5 Correct 1 ms 6960 KB Output is correct
6 Correct 1 ms 7004 KB Output is correct

Subtask #2
23.0 / 23.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 7004 KB Output is correct
2 Correct 1 ms 7004 KB Output is correct
3 Correct 1 ms 7004 KB Output is correct
4 Correct 1 ms 7004 KB Output is correct
5 Correct 1 ms 6960 KB Output is correct
6 Correct 1 ms 7004 KB Output is correct
7 Correct 4 ms 12892 KB Output is correct
8 Correct 5 ms 13092 KB Output is correct
9 Correct 7 ms 14940 KB Output is correct
10 Correct 4 ms 12892 KB Output is correct
11 Correct 3 ms 12892 KB Output is correct
12 Correct 3 ms 12892 KB Output is correct

Subtask #3
66.0 / 66.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 7004 KB Output is correct
2 Correct 1 ms 7004 KB Output is correct
3 Correct 1 ms 7004 KB Output is correct
4 Correct 1 ms 7004 KB Output is correct
5 Correct 1 ms 6960 KB Output is correct
6 Correct 1 ms 7004 KB Output is correct
7 Correct 4 ms 12892 KB Output is correct
8 Correct 5 ms 13092 KB Output is correct
9 Correct 7 ms 14940 KB Output is correct
10 Correct 4 ms 12892 KB Output is correct
11 Correct 3 ms 12892 KB Output is correct
12 Correct 3 ms 12892 KB Output is correct
13 Correct 120 ms 61524 KB Output is correct
14 Correct 153 ms 61588 KB Output is correct
15 Correct 208 ms 157336 KB Output is correct
16 Correct 91 ms 61524 KB Output is correct
17 Correct 88 ms 61532 KB Output is correct
18 Correct 88 ms 61524 KB Output is correct