oj.uz

Submission #366302

# Submission time Handle Problem Language Result Execution time Memory
366302 2021-02-13T20:28:07 Z arman_ferdous Monochrome Points (JOI20_monochrome) C++17
35 / 100
 1977 ms 12380 KB 
#include <bits/stdc++.h>
using namespace std;

#define fi first
#define se second
#define pb push_back
#define sz(v) (int)v.size()
#define all(v) v.begin(),v.end()
#define dbg(x) cerr << #x << " is " << x << "\n";
#define cum cerr << "came\n";

using ll = long long;
using ii = pair<ll,ll>;

const int N = 4e5+10;

int n;
char s[N];

struct event {
  int x, y;
  int type;
  bool operator<(event o) const {
    return x < o.x;
  }
};

struct BIT {
  int b[N];
  void upd(int pos, int x) { while(pos < N) b[pos] += x, pos += pos&-pos; }
  ll get(int pos, int r = 0) { while(pos) r += b[pos], pos -= pos&-pos; return r; }
}bit;

vector<event> e;

int vis[N];
vector<pair<int, int>> segs;

ll getcost() {
  e.clear();
  for(auto it : segs) {
    e.pb({it.fi + 1, it.se + 1, 0});
    e.pb({it.se + 1, it.fi + 1, 1});
  } sort(all(e));

  ll ret = 0;
  for(auto i : e) {
    if(i.type == 0) {
      ret += bit.get(i.y - 1);
      bit.upd(i.y, +1);
    }
    else {
      bit.upd(i.x, -1);
    }
  }
  return ret;
}

ll solve(int p, int q) {
  segs.clear();
  for(int i = 0; i < n + n; i++) vis[i] = 0;
  segs.pb({p, q});
  vis[p] = vis[q] = 1;

  int matched = 1;
  int i = p, j = q;
  while(matched < n) {
    while(vis[i] || s[i] != s[p]) {
      i++;
      if(i == n + n) i = 0;
    }

    while(s[i] == s[j] || vis[j]) {
      j++; 
      if(j == n + n) j = 0;
    }

    vis[j] = vis[i] = 1;
    segs.pb({min(i, j), max(i, j)});
    matched++;
  }

  // for(auto it : segs)
  //   cout << it.fi + 1 << " " << it.se + 1 << endl;
  // cout << "cost = " << getcost() << endl;

  return getcost();
}

vector<int> pos;

int main() {
  ll ans = 0;
  scanf("%d %s", &n, s);
  for(int i = 1; i < n + n; i++) if(s[0] != s[i])
    pos.pb(i);

  int lo = 0, hi = sz(pos) - 1;
  while(hi - lo >= 3) {
    int mid1 = (lo + lo + hi) / 3;
    int mid2 = (lo + hi + hi) / 3;

    int f1 = solve(0, pos[mid1]);
    int f2 = solve(0, pos[mid2]);

    if(f1 >= f2) hi = mid2 - 1;
    else lo = mid1 + 1;
  }
  for(int i = lo; i <= hi; i++) 
    ans = max(ans, solve(0, pos[i]));

  printf("%lld\n", ans);
  return 0;
}

Compilation message

monochrome.cpp: In function 'int main()':
monochrome.cpp:94:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   94 |   scanf("%d %s", &n, s);
      |   ~~~~~^~~~~~~~~~~~~~~~

Subtask #1
4.0 / 4.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 364 KB Output is correct
2 Correct 0 ms 364 KB Output is correct
3 Correct 1 ms 364 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 1 ms 364 KB Output is correct
8 Correct 1 ms 364 KB Output is correct
9 Correct 1 ms 364 KB Output is correct
10 Correct 0 ms 364 KB Output is correct
11 Correct 0 ms 364 KB Output is correct
12 Correct 0 ms 364 KB Output is correct
13 Correct 0 ms 364 KB Output is correct

Subtask #2
21.0 / 21.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 364 KB Output is correct
2 Correct 0 ms 364 KB Output is correct
3 Correct 1 ms 364 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 1 ms 364 KB Output is correct
8 Correct 1 ms 364 KB Output is correct
9 Correct 1 ms 364 KB Output is correct
10 Correct 0 ms 364 KB Output is correct
11 Correct 0 ms 364 KB Output is correct
12 Correct 0 ms 364 KB Output is correct
13 Correct 0 ms 364 KB Output is correct
14 Correct 2 ms 364 KB Output is correct
15 Correct 2 ms 364 KB Output is correct
16 Correct 2 ms 364 KB Output is correct
17 Correct 2 ms 364 KB Output is correct
18 Correct 2 ms 364 KB Output is correct
19 Correct 2 ms 364 KB Output is correct
20 Correct 2 ms 364 KB Output is correct
21 Correct 2 ms 364 KB Output is correct
22 Correct 2 ms 364 KB Output is correct
23 Correct 1 ms 364 KB Output is correct
24 Correct 2 ms 364 KB Output is correct
25 Correct 2 ms 364 KB Output is correct
26 Correct 2 ms 364 KB Output is correct
27 Correct 2 ms 364 KB Output is correct
28 Correct 2 ms 364 KB Output is correct
29 Correct 2 ms 364 KB Output is correct
30 Correct 2 ms 364 KB Output is correct
31 Correct 2 ms 364 KB Output is correct
32 Correct 2 ms 364 KB Output is correct
33 Correct 2 ms 364 KB Output is correct

Subtask #3
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 364 KB Output is correct
2 Correct 0 ms 364 KB Output is correct
3 Correct 1 ms 364 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 1 ms 364 KB Output is correct
8 Correct 1 ms 364 KB Output is correct
9 Correct 1 ms 364 KB Output is correct
10 Correct 0 ms 364 KB Output is correct
11 Correct 0 ms 364 KB Output is correct
12 Correct 0 ms 364 KB Output is correct
13 Correct 0 ms 364 KB Output is correct
14 Correct 2 ms 364 KB Output is correct
15 Correct 2 ms 364 KB Output is correct
16 Correct 2 ms 364 KB Output is correct
17 Correct 2 ms 364 KB Output is correct
18 Correct 2 ms 364 KB Output is correct
19 Correct 2 ms 364 KB Output is correct
20 Correct 2 ms 364 KB Output is correct
21 Correct 2 ms 364 KB Output is correct
22 Correct 2 ms 364 KB Output is correct
23 Correct 1 ms 364 KB Output is correct
24 Correct 2 ms 364 KB Output is correct
25 Correct 2 ms 364 KB Output is correct
26 Correct 2 ms 364 KB Output is correct
27 Correct 2 ms 364 KB Output is correct
28 Correct 2 ms 364 KB Output is correct
29 Correct 2 ms 364 KB Output is correct
30 Correct 2 ms 364 KB Output is correct
31 Correct 2 ms 364 KB Output is correct
32 Correct 2 ms 364 KB Output is correct
33 Correct 2 ms 364 KB Output is correct
34 Correct 12 ms 492 KB Output is correct
35 Correct 13 ms 492 KB Output is correct
36 Correct 13 ms 492 KB Output is correct
37 Correct 12 ms 492 KB Output is correct
38 Correct 11 ms 620 KB Output is correct
39 Correct 11 ms 492 KB Output is correct
40 Correct 10 ms 492 KB Output is correct
41 Correct 10 ms 492 KB Output is correct
42 Correct 13 ms 492 KB Output is correct
43 Correct 11 ms 492 KB Output is correct
44 Correct 10 ms 492 KB Output is correct
45 Correct 11 ms 492 KB Output is correct
46 Correct 12 ms 492 KB Output is correct
47 Correct 11 ms 512 KB Output is correct
48 Correct 12 ms 492 KB Output is correct
49 Correct 12 ms 492 KB Output is correct
50 Correct 11 ms 492 KB Output is correct
51 Correct 11 ms 492 KB Output is correct
52 Correct 11 ms 492 KB Output is correct

Subtask #4
0.0 / 65.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 364 KB Output is correct
2 Correct 0 ms 364 KB Output is correct
3 Correct 1 ms 364 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 1 ms 364 KB Output is correct
8 Correct 1 ms 364 KB Output is correct
9 Correct 1 ms 364 KB Output is correct
10 Correct 0 ms 364 KB Output is correct
11 Correct 0 ms 364 KB Output is correct
12 Correct 0 ms 364 KB Output is correct
13 Correct 0 ms 364 KB Output is correct
14 Correct 2 ms 364 KB Output is correct
15 Correct 2 ms 364 KB Output is correct
16 Correct 2 ms 364 KB Output is correct
17 Correct 2 ms 364 KB Output is correct
18 Correct 2 ms 364 KB Output is correct
19 Correct 2 ms 364 KB Output is correct
20 Correct 2 ms 364 KB Output is correct
21 Correct 2 ms 364 KB Output is correct
22 Correct 2 ms 364 KB Output is correct
23 Correct 1 ms 364 KB Output is correct
24 Correct 2 ms 364 KB Output is correct
25 Correct 2 ms 364 KB Output is correct
26 Correct 2 ms 364 KB Output is correct
27 Correct 2 ms 364 KB Output is correct
28 Correct 2 ms 364 KB Output is correct
29 Correct 2 ms 364 KB Output is correct
30 Correct 2 ms 364 KB Output is correct
31 Correct 2 ms 364 KB Output is correct
32 Correct 2 ms 364 KB Output is correct
33 Correct 2 ms 364 KB Output is correct
34 Correct 12 ms 492 KB Output is correct
35 Correct 13 ms 492 KB Output is correct
36 Correct 13 ms 492 KB Output is correct
37 Correct 12 ms 492 KB Output is correct
38 Correct 11 ms 620 KB Output is correct
39 Correct 11 ms 492 KB Output is correct
40 Correct 10 ms 492 KB Output is correct
41 Correct 10 ms 492 KB Output is correct
42 Correct 13 ms 492 KB Output is correct
43 Correct 11 ms 492 KB Output is correct
44 Correct 10 ms 492 KB Output is correct
45 Correct 11 ms 492 KB Output is correct
46 Correct 12 ms 492 KB Output is correct
47 Correct 11 ms 512 KB Output is correct
48 Correct 12 ms 492 KB Output is correct
49 Correct 12 ms 492 KB Output is correct
50 Correct 11 ms 492 KB Output is correct
51 Correct 11 ms 492 KB Output is correct
52 Correct 11 ms 492 KB Output is correct
53 Incorrect 1977 ms 12380 KB Output isn't correct
54 Halted 0 ms 0 KB -