Submission #333968

# Submission time Handle Problem Language Result Execution time Memory
333968 2020-12-08T04:07:46 Z VROOM_VARUN Nafta (COI15_nafta) C++14
100 / 100
970 ms 157548 KB
/*
ID: varunra2
LANG: C++
TASK: nafta
*/

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

#ifdef DEBUG
#include "lib/debug.h"
#define debug(...) cerr << "[" << #__VA_ARGS__ << "]:", debug_out(__VA_ARGS__)
#define debug_arr(...) \
  cerr << "[" << #__VA_ARGS__ << "]:", debug_arr(__VA_ARGS__)
#pragma GCC diagnostic ignored "-Wsign-compare"
//#pragma GCC diagnostic ignored "-Wunused-parameter"
//#pragma GCC diagnostic ignored "-Wunused-variable"
#else
#define debug(...) 42
#endif

#define EPS 1e-9
#define IN(A, B, C) assert(B <= A && A <= C)
#define INF (int)1e9
#define MEM(a, b) memset(a, (b), sizeof(a))
#define MOD 1000000007
#define MP make_pair
#define PB push_back
#define all(cont) cont.begin(), cont.end()
#define rall(cont) cont.end(), cont.begin()
#define x first
#define y second

const double PI = acos(-1.0);
typedef long long ll;
typedef long double ld;
typedef pair<int, int> PII;
typedef map<int, int> MPII;
typedef multiset<int> MSETI;
typedef set<int> SETI;
typedef set<string> SETS;
typedef vector<int> VI;
typedef vector<PII> VII;
typedef vector<VI> VVI;
typedef vector<string> VS;

#define rep(i, a, b) for (int i = a; i < (b); ++i)
#define trav(a, x) for (auto& a : x)
#define sz(x) (int)(x).size()
typedef pair<int, int> pii;
typedef vector<int> vi;
#pragma GCC diagnostic ignored "-Wsign-compare"
// util functions

int n, m;

int hsh(int u, int v) { return u * m + v; }

int hsh(PII u) { return u.x * m + u.y; }

PII unhsh(int u) { return MP(u / m, u % m); }

int xunhsh(int u) { return u % m; }

struct dsu {
  int n;
  VI par;
  VI siz;
  VI cost;

  void init(int _n) {
    n = _n;
    siz.assign(n, 1);
    par.resize(n);
    cost.resize(n, 0);
    iota(all(par), 0);
  }

  void set(int ind, int val) { cost[ind] = val; }

  int find(int x) {
    while (par[x] != par[par[x]]) par[x] = par[par[x]];
    return par[x];
  }

  bool same(int x, int y) { return find(x) == find(y); }

  void merge(int x, int y) {
    if (same(x, y)) return;
    x = find(x);
    y = find(y);
    if (siz[x] < siz[y]) swap(x, y);
    par[y] = x;
    siz[x] += siz[y];
    cost[x] += cost[y];
  }

  int gcost(int x) { return cost[find(x)]; }
} dsu1;

VVI grid;
VVI cost;
VI sum;
vector<vector<bool>> vis;
int gp = 0;
VVI group;
VI sums;
VI start;

VI dx = {0, -1, 0, 1};
VI dy = {1, 0, -1, 0};

bool inbnds(int i, int j) { return i >= 0 and i < n and j >= 0 and j < m; }

int mn;

void dfs(int nx, int ny) {
  if (!inbnds(nx, ny)) return;
  if (grid[nx][ny] == -1) return;
  if (vis[nx][ny]) return;
  vis[nx][ny] = true;
  group[nx][ny] = gp;
  mn = min(mn, ny);
  sums.back() += grid[nx][ny];
  for (int dir = 0; dir < 4; dir++) {
    dfs(nx + dx[dir], ny + dy[dir]);
  }
}

void calc(int ind) {
  VI use;
  for (int i = 0; i < n; i++) {
    if (vis[i][ind]) use.PB(group[i][ind]);
  }
  sort(all(use));
  use.resize(unique(all(use)) - use.begin());
  int sum = 0;
  VVI events;
  trav(x, use) sum += sums[x], events.PB({start[x], 0, -sums[x]});
  for (int i = 0; i < ind; i++) {
    events.PB({i, 1});
  }
  cost[ind + 1][0] = sum;
  sort(all(events));

  trav(x, events) {
    if (x[1] == 0) {
      sum += x[2];
    } else
      cost[ind + 1][x[0] + 1] = sum;
  }
}
vector<long long> dp_before, dp_cur;

void init() {
  grid.resize(n);
  trav(x, grid) x.resize(m);
  cost.resize(m + 1);
  trav(x, cost) x.assign(m + 1, 0);
  dp_before.assign(m + 1, 0);
  dp_cur.assign(m + 1, 0);
  group.resize(n);
  trav(x, group) x.resize(m);
  vis.resize(n);
  trav(x, vis) x.assign(m, false);
}

long long C(int i, int j) { return cost[j][i]; }

// compute dp_cur[l], ... dp_cur[r] (inclusive)
void compute(int l, int r, int optl, int optr) {
  if (l > r) return;
  int mid = (l + r) >> 1;
  pair<int, int> best = {-1, -1};

  for (int k = optl; k <= min(mid, optr); k++) {
    best = max(best, {dp_before[k] + C(k, mid), k});
  }

  dp_cur[mid] = best.first;
  int opt = best.second;

  compute(l, mid - 1, optl, opt);
  compute(mid + 1, r, opt, optr);
}

void compute1() {
  for (int i = 0; i <= m; i++) {
    for (int j = 0; j <= i; j++) {
      dp_cur[i] = max(dp_cur[i], dp_before[j] + C(j, i));
    }
  }
}

int main() {
  cin.sync_with_stdio(0);
  cin.tie(0);

  cin >> n >> m;
  init();
  dsu1.init(n * m);

  rep(i, 0, n) rep(j, 0, m) {
    char c;
    cin >> c;
    if (c == '.')
      grid[i][j] = -1;
    else
      grid[i][j] = c - '0';
    // dsu1.set(hsh(i, j), grid[i][j]);
  }

  for (int i = 0; i < n; i++) {
    for (int j = 0; j < m; j++) {
      if (vis[i][j]) continue;
      if (grid[i][j] == -1) continue;
      mn = INF;
      sums.PB(0);
      dfs(i, j);
      gp++;
      start.PB(mn);
    }
  }

  for (int i = 0; i < m; i++) {
    calc(i);
  }

  for (int i = 0; i < m; i++) {
    compute(0, m, 0, m);
    cout << *max_element(all(dp_cur)) << '\n';
    swap(dp_cur, dp_before);
  }

  return 0;
}
# Verdict Execution time Memory Grader output
1 Correct 1 ms 364 KB Output is correct
2 Correct 1 ms 364 KB Output is correct
3 Correct 1 ms 492 KB Output is correct
4 Correct 1 ms 364 KB Output is correct
5 Correct 1 ms 364 KB Output is correct
6 Correct 1 ms 364 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 1 ms 364 KB Output is correct
2 Correct 1 ms 364 KB Output is correct
3 Correct 1 ms 492 KB Output is correct
4 Correct 1 ms 364 KB Output is correct
5 Correct 1 ms 364 KB Output is correct
6 Correct 1 ms 364 KB Output is correct
7 Correct 17 ms 2668 KB Output is correct
8 Correct 19 ms 2540 KB Output is correct
9 Correct 18 ms 3820 KB Output is correct
10 Correct 17 ms 2668 KB Output is correct
11 Correct 16 ms 2540 KB Output is correct
12 Correct 16 ms 2540 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 1 ms 364 KB Output is correct
2 Correct 1 ms 364 KB Output is correct
3 Correct 1 ms 492 KB Output is correct
4 Correct 1 ms 364 KB Output is correct
5 Correct 1 ms 364 KB Output is correct
6 Correct 1 ms 364 KB Output is correct
7 Correct 17 ms 2668 KB Output is correct
8 Correct 19 ms 2540 KB Output is correct
9 Correct 18 ms 3820 KB Output is correct
10 Correct 17 ms 2668 KB Output is correct
11 Correct 16 ms 2540 KB Output is correct
12 Correct 16 ms 2540 KB Output is correct
13 Correct 864 ms 99468 KB Output is correct
14 Correct 970 ms 98496 KB Output is correct
15 Correct 927 ms 157548 KB Output is correct
16 Correct 849 ms 101332 KB Output is correct
17 Correct 849 ms 99808 KB Output is correct
18 Correct 856 ms 99668 KB Output is correct