oj.uz

Submission #366309

# Submission time Handle Problem Language Result Execution time Memory
366309 2021-02-13T20:48:25 Z arman_ferdous Monochrome Points (JOI20_monochrome) C++17
100 / 100
 1048 ms 18024 KB 
#include <bits/stdc++.h>
#define int long long
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 = 5e5+10;

int n;
char s[N];

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;

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

int l[N], r[N];

ll getcost() {
  for(auto it : segs) {
    l[it.se] = it.fi;
    r[it.fi] = it.se;
    l[it.fi] = r[it.se] = 0;
  }

  ll ret = 0;
  for(int i = 1; i <= n + n; i++) {
    if(l[i] == 0) {
      ret += bit.get(r[i] - 1);
      bit.upd(r[i], +1);
    }
    else bit.upd(i, -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 + 1, q + 1});
  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) + 1, max(i, j) + 1});
    matched++;
  }

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

  return getcost();
}

vector<int> pos;

int32_t main() {
  ll ans = 0;
  scanf("%lld %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 >= 10) {
    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 'int32_t main()':
monochrome.cpp:85:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   85 |   scanf("%lld %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 1 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 0 ms 364 KB Output is correct
10 Correct 1 ms 364 KB Output is correct
11 Correct 1 ms 364 KB Output is correct
12 Correct 1 ms 364 KB Output is correct
13 Correct 1 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 1 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 0 ms 364 KB Output is correct
10 Correct 1 ms 364 KB Output is correct
11 Correct 1 ms 364 KB Output is correct
12 Correct 1 ms 364 KB Output is correct
13 Correct 1 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 384 KB Output is correct
18 Correct 2 ms 364 KB Output is correct
19 Correct 2 ms 364 KB Output is correct
20 Correct 1 ms 364 KB Output is correct
21 Correct 2 ms 364 KB Output is correct
22 Correct 1 ms 364 KB Output is correct
23 Correct 1 ms 364 KB Output is correct
24 Correct 1 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 1 ms 364 KB Output is correct
28 Correct 1 ms 364 KB Output is correct
29 Correct 1 ms 364 KB Output is correct
30 Correct 2 ms 364 KB Output is correct
31 Correct 1 ms 364 KB Output is correct
32 Correct 1 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 1 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 0 ms 364 KB Output is correct
10 Correct 1 ms 364 KB Output is correct
11 Correct 1 ms 364 KB Output is correct
12 Correct 1 ms 364 KB Output is correct
13 Correct 1 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 384 KB Output is correct
18 Correct 2 ms 364 KB Output is correct
19 Correct 2 ms 364 KB Output is correct
20 Correct 1 ms 364 KB Output is correct
21 Correct 2 ms 364 KB Output is correct
22 Correct 1 ms 364 KB Output is correct
23 Correct 1 ms 364 KB Output is correct
24 Correct 1 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 1 ms 364 KB Output is correct
28 Correct 1 ms 364 KB Output is correct
29 Correct 1 ms 364 KB Output is correct
30 Correct 2 ms 364 KB Output is correct
31 Correct 1 ms 364 KB Output is correct
32 Correct 1 ms 364 KB Output is correct
33 Correct 2 ms 364 KB Output is correct
34 Correct 8 ms 620 KB Output is correct
35 Correct 8 ms 620 KB Output is correct
36 Correct 8 ms 620 KB Output is correct
37 Correct 8 ms 620 KB Output is correct
38 Correct 7 ms 620 KB Output is correct
39 Correct 7 ms 620 KB Output is correct
40 Correct 7 ms 620 KB Output is correct
41 Correct 6 ms 620 KB Output is correct
42 Correct 8 ms 620 KB Output is correct
43 Correct 7 ms 620 KB Output is correct
44 Correct 7 ms 620 KB Output is correct
45 Correct 7 ms 620 KB Output is correct
46 Correct 7 ms 620 KB Output is correct
47 Correct 7 ms 620 KB Output is correct
48 Correct 7 ms 620 KB Output is correct
49 Correct 6 ms 620 KB Output is correct
50 Correct 6 ms 620 KB Output is correct
51 Correct 7 ms 620 KB Output is correct
52 Correct 7 ms 620 KB Output is correct

Subtask #4
65.0 / 65.0

# 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 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 0 ms 364 KB Output is correct
10 Correct 1 ms 364 KB Output is correct
11 Correct 1 ms 364 KB Output is correct
12 Correct 1 ms 364 KB Output is correct
13 Correct 1 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 384 KB Output is correct
18 Correct 2 ms 364 KB Output is correct
19 Correct 2 ms 364 KB Output is correct
20 Correct 1 ms 364 KB Output is correct
21 Correct 2 ms 364 KB Output is correct
22 Correct 1 ms 364 KB Output is correct
23 Correct 1 ms 364 KB Output is correct
24 Correct 1 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 1 ms 364 KB Output is correct
28 Correct 1 ms 364 KB Output is correct
29 Correct 1 ms 364 KB Output is correct
30 Correct 2 ms 364 KB Output is correct
31 Correct 1 ms 364 KB Output is correct
32 Correct 1 ms 364 KB Output is correct
33 Correct 2 ms 364 KB Output is correct
34 Correct 8 ms 620 KB Output is correct
35 Correct 8 ms 620 KB Output is correct
36 Correct 8 ms 620 KB Output is correct
37 Correct 8 ms 620 KB Output is correct
38 Correct 7 ms 620 KB Output is correct
39 Correct 7 ms 620 KB Output is correct
40 Correct 7 ms 620 KB Output is correct
41 Correct 6 ms 620 KB Output is correct
42 Correct 8 ms 620 KB Output is correct
43 Correct 7 ms 620 KB Output is correct
44 Correct 7 ms 620 KB Output is correct
45 Correct 7 ms 620 KB Output is correct
46 Correct 7 ms 620 KB Output is correct
47 Correct 7 ms 620 KB Output is correct
48 Correct 7 ms 620 KB Output is correct
49 Correct 6 ms 620 KB Output is correct
50 Correct 6 ms 620 KB Output is correct
51 Correct 7 ms 620 KB Output is correct
52 Correct 7 ms 620 KB Output is correct
53 Correct 1047 ms 17496 KB Output is correct
54 Correct 1048 ms 17752 KB Output is correct
55 Correct 982 ms 16984 KB Output is correct
56 Correct 1006 ms 17112 KB Output is correct
57 Correct 762 ms 17116 KB Output is correct
58 Correct 802 ms 17752 KB Output is correct
59 Correct 772 ms 16984 KB Output is correct
60 Correct 809 ms 17112 KB Output is correct
61 Correct 829 ms 17368 KB Output is correct
62 Correct 822 ms 17368 KB Output is correct
63 Correct 848 ms 17240 KB Output is correct
64 Correct 779 ms 17240 KB Output is correct
65 Correct 814 ms 16344 KB Output is correct
66 Correct 794 ms 17112 KB Output is correct
67 Correct 800 ms 17100 KB Output is correct
68 Correct 741 ms 16344 KB Output is correct
69 Correct 790 ms 17496 KB Output is correct
70 Correct 722 ms 15960 KB Output is correct
71 Correct 763 ms 16988 KB Output is correct
72 Correct 754 ms 16988 KB Output is correct
73 Correct 824 ms 18024 KB Output is correct