Submission #639571

# Submission time Handle Problem Language Result Execution time Memory
639571 2022-09-10T16:21:12 Z valerikk Monochrome Points (JOI20_monochrome) C++17
100 / 100
1198 ms 54140 KB
#include <bits/stdc++.h>

using namespace std;

const int N = 4e5 + 7;

int fen[N];
vector<int> start[N], finish[N];

void add_fen(int i, int val) {
	for (++i; i < N; i += i & -i) {
		fen[i] += val;
	}
}

int get_fen(int i) {
	int res = 0;
	for (; i > 0; i -= i & -i) {
		res += fen[i];
	}
	return res;
}

char s[N];

int main() {
	int n;
	scanf("%d", &n);
	scanf("%s", s);
	vector<int> black, white;
	for (int i = 0; i < 2 * n; ++i) {
		if (s[i] == 'W') {
			white.push_back(i);
		} else {
			black.push_back(i);
		}
	}
	sort(black.begin(), black.end());
	sort(white.begin(), white.end());
	auto calc = [&](int k) {
		k %= n;
		for (int i = 0; i < 2 * n + 1; ++i) {
			start[i].clear();
			finish[i].clear();
		}
		memset(fen, 0, sizeof fen);
		vector<pair<int, int>> segments;
		for (int i = 0; i < n; ++i) {
			int x = black[i], y = white[(i + k) % n];
			segments.push_back({min(x, y), max(x, y)});
		}
		for (int i = 0; i < n; ++i) {
			start[segments[i].first + 1].push_back(i);
			finish[segments[i].second].push_back(i);
		}
		long long res = 0;
		int tot = 0;
		for (int i = 0; i < 2 * n; ++i) {
			for (int j : start[i]) {
				++tot;
				add_fen(segments[j].first, 1);
			}
			for (int j : finish[i]) {
				--tot;
				add_fen(segments[j].first, -1);
			}
			for (int j : finish[i]) {
				res += tot - get_fen(segments[j].first + 1);
			}
		}
		return res;
	};
	if (n == 1) {
		printf("%lld\n", calc(0));
		return 0;
	}
	vector<int> f(n + 1);
	for (int i = 0; i < n + 1; ++i) {
		f[i] = i % n;
	}
	vector<long long> mem(n + 1, -1);
	auto get = [&](int x) {
		return mem[x] == -1 ? mem[x] = calc(f[x]) : mem[x];
	};
	if (get(0) < get(1)) {
		reverse(f.begin() + 1, f.end());
	}
	int l = 0, r = n;
	while (r - l > 1) {
		int m = (l + r) / 2;
		if (get(m) < get(0)) {
			l = m;
		} else {
			r = m;
		}
	}
	r = n;
	while (r - l > 2) {
		int m = (l + r) / 2;
		if (get(m) < get(m + 1)) {
			l = m;
		} else {
			r = m + 1;
		}
	}
	long long ans = 0;
	for (int k = l; k <= r; ++k) {
		ans = max(ans, get(k));
	}
	printf("%lld\n", ans);
	return 0;
}

Compilation message

monochrome.cpp: In function 'int main()':
monochrome.cpp:28:7: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   28 |  scanf("%d", &n);
      |  ~~~~~^~~~~~~~~~
monochrome.cpp:29:7: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   29 |  scanf("%s", s);
      |  ~~~~~^~~~~~~~~
# Verdict Execution time Memory Grader output
1 Correct 11 ms 20564 KB Output is correct
2 Correct 11 ms 20624 KB Output is correct
3 Correct 11 ms 20564 KB Output is correct
4 Correct 11 ms 20564 KB Output is correct
5 Correct 11 ms 20564 KB Output is correct
6 Correct 11 ms 20564 KB Output is correct
7 Correct 11 ms 20532 KB Output is correct
8 Correct 11 ms 20552 KB Output is correct
9 Correct 11 ms 20660 KB Output is correct
10 Correct 11 ms 20564 KB Output is correct
11 Correct 12 ms 20656 KB Output is correct
12 Correct 11 ms 20628 KB Output is correct
13 Correct 10 ms 20632 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 11 ms 20564 KB Output is correct
2 Correct 11 ms 20624 KB Output is correct
3 Correct 11 ms 20564 KB Output is correct
4 Correct 11 ms 20564 KB Output is correct
5 Correct 11 ms 20564 KB Output is correct
6 Correct 11 ms 20564 KB Output is correct
7 Correct 11 ms 20532 KB Output is correct
8 Correct 11 ms 20552 KB Output is correct
9 Correct 11 ms 20660 KB Output is correct
10 Correct 11 ms 20564 KB Output is correct
11 Correct 12 ms 20656 KB Output is correct
12 Correct 11 ms 20628 KB Output is correct
13 Correct 10 ms 20632 KB Output is correct
14 Correct 15 ms 20680 KB Output is correct
15 Correct 13 ms 20620 KB Output is correct
16 Correct 15 ms 20716 KB Output is correct
17 Correct 13 ms 20692 KB Output is correct
18 Correct 12 ms 20692 KB Output is correct
19 Correct 12 ms 20692 KB Output is correct
20 Correct 12 ms 20688 KB Output is correct
21 Correct 12 ms 20692 KB Output is correct
22 Correct 14 ms 20704 KB Output is correct
23 Correct 12 ms 20692 KB Output is correct
24 Correct 12 ms 20564 KB Output is correct
25 Correct 12 ms 20684 KB Output is correct
26 Correct 12 ms 20692 KB Output is correct
27 Correct 12 ms 20692 KB Output is correct
28 Correct 12 ms 20692 KB Output is correct
29 Correct 12 ms 20692 KB Output is correct
30 Correct 16 ms 20692 KB Output is correct
31 Correct 12 ms 20688 KB Output is correct
32 Correct 13 ms 20692 KB Output is correct
33 Correct 13 ms 20692 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 11 ms 20564 KB Output is correct
2 Correct 11 ms 20624 KB Output is correct
3 Correct 11 ms 20564 KB Output is correct
4 Correct 11 ms 20564 KB Output is correct
5 Correct 11 ms 20564 KB Output is correct
6 Correct 11 ms 20564 KB Output is correct
7 Correct 11 ms 20532 KB Output is correct
8 Correct 11 ms 20552 KB Output is correct
9 Correct 11 ms 20660 KB Output is correct
10 Correct 11 ms 20564 KB Output is correct
11 Correct 12 ms 20656 KB Output is correct
12 Correct 11 ms 20628 KB Output is correct
13 Correct 10 ms 20632 KB Output is correct
14 Correct 15 ms 20680 KB Output is correct
15 Correct 13 ms 20620 KB Output is correct
16 Correct 15 ms 20716 KB Output is correct
17 Correct 13 ms 20692 KB Output is correct
18 Correct 12 ms 20692 KB Output is correct
19 Correct 12 ms 20692 KB Output is correct
20 Correct 12 ms 20688 KB Output is correct
21 Correct 12 ms 20692 KB Output is correct
22 Correct 14 ms 20704 KB Output is correct
23 Correct 12 ms 20692 KB Output is correct
24 Correct 12 ms 20564 KB Output is correct
25 Correct 12 ms 20684 KB Output is correct
26 Correct 12 ms 20692 KB Output is correct
27 Correct 12 ms 20692 KB Output is correct
28 Correct 12 ms 20692 KB Output is correct
29 Correct 12 ms 20692 KB Output is correct
30 Correct 16 ms 20692 KB Output is correct
31 Correct 12 ms 20688 KB Output is correct
32 Correct 13 ms 20692 KB Output is correct
33 Correct 13 ms 20692 KB Output is correct
34 Correct 22 ms 20948 KB Output is correct
35 Correct 18 ms 20968 KB Output is correct
36 Correct 18 ms 20860 KB Output is correct
37 Correct 18 ms 20852 KB Output is correct
38 Correct 17 ms 20848 KB Output is correct
39 Correct 18 ms 20848 KB Output is correct
40 Correct 20 ms 20840 KB Output is correct
41 Correct 17 ms 20820 KB Output is correct
42 Correct 18 ms 20948 KB Output is correct
43 Correct 17 ms 20908 KB Output is correct
44 Correct 22 ms 20948 KB Output is correct
45 Correct 21 ms 20800 KB Output is correct
46 Correct 19 ms 20820 KB Output is correct
47 Correct 18 ms 20872 KB Output is correct
48 Correct 18 ms 20896 KB Output is correct
49 Correct 17 ms 20924 KB Output is correct
50 Correct 16 ms 20856 KB Output is correct
51 Correct 14 ms 20808 KB Output is correct
52 Correct 17 ms 20988 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 11 ms 20564 KB Output is correct
2 Correct 11 ms 20624 KB Output is correct
3 Correct 11 ms 20564 KB Output is correct
4 Correct 11 ms 20564 KB Output is correct
5 Correct 11 ms 20564 KB Output is correct
6 Correct 11 ms 20564 KB Output is correct
7 Correct 11 ms 20532 KB Output is correct
8 Correct 11 ms 20552 KB Output is correct
9 Correct 11 ms 20660 KB Output is correct
10 Correct 11 ms 20564 KB Output is correct
11 Correct 12 ms 20656 KB Output is correct
12 Correct 11 ms 20628 KB Output is correct
13 Correct 10 ms 20632 KB Output is correct
14 Correct 15 ms 20680 KB Output is correct
15 Correct 13 ms 20620 KB Output is correct
16 Correct 15 ms 20716 KB Output is correct
17 Correct 13 ms 20692 KB Output is correct
18 Correct 12 ms 20692 KB Output is correct
19 Correct 12 ms 20692 KB Output is correct
20 Correct 12 ms 20688 KB Output is correct
21 Correct 12 ms 20692 KB Output is correct
22 Correct 14 ms 20704 KB Output is correct
23 Correct 12 ms 20692 KB Output is correct
24 Correct 12 ms 20564 KB Output is correct
25 Correct 12 ms 20684 KB Output is correct
26 Correct 12 ms 20692 KB Output is correct
27 Correct 12 ms 20692 KB Output is correct
28 Correct 12 ms 20692 KB Output is correct
29 Correct 12 ms 20692 KB Output is correct
30 Correct 16 ms 20692 KB Output is correct
31 Correct 12 ms 20688 KB Output is correct
32 Correct 13 ms 20692 KB Output is correct
33 Correct 13 ms 20692 KB Output is correct
34 Correct 22 ms 20948 KB Output is correct
35 Correct 18 ms 20968 KB Output is correct
36 Correct 18 ms 20860 KB Output is correct
37 Correct 18 ms 20852 KB Output is correct
38 Correct 17 ms 20848 KB Output is correct
39 Correct 18 ms 20848 KB Output is correct
40 Correct 20 ms 20840 KB Output is correct
41 Correct 17 ms 20820 KB Output is correct
42 Correct 18 ms 20948 KB Output is correct
43 Correct 17 ms 20908 KB Output is correct
44 Correct 22 ms 20948 KB Output is correct
45 Correct 21 ms 20800 KB Output is correct
46 Correct 19 ms 20820 KB Output is correct
47 Correct 18 ms 20872 KB Output is correct
48 Correct 18 ms 20896 KB Output is correct
49 Correct 17 ms 20924 KB Output is correct
50 Correct 16 ms 20856 KB Output is correct
51 Correct 14 ms 20808 KB Output is correct
52 Correct 17 ms 20988 KB Output is correct
53 Correct 1198 ms 53396 KB Output is correct
54 Correct 1185 ms 53112 KB Output is correct
55 Correct 1127 ms 52036 KB Output is correct
56 Correct 1142 ms 52024 KB Output is correct
57 Correct 935 ms 51276 KB Output is correct
58 Correct 980 ms 51300 KB Output is correct
59 Correct 1028 ms 52552 KB Output is correct
60 Correct 992 ms 50648 KB Output is correct
61 Correct 1104 ms 50996 KB Output is correct
62 Correct 1061 ms 51984 KB Output is correct
63 Correct 1112 ms 52784 KB Output is correct
64 Correct 950 ms 44980 KB Output is correct
65 Correct 1045 ms 51400 KB Output is correct
66 Correct 945 ms 42916 KB Output is correct
67 Correct 933 ms 43140 KB Output is correct
68 Correct 876 ms 41892 KB Output is correct
69 Correct 976 ms 49628 KB Output is correct
70 Correct 848 ms 44548 KB Output is correct
71 Correct 439 ms 41604 KB Output is correct
72 Correct 429 ms 41776 KB Output is correct
73 Correct 1068 ms 54140 KB Output is correct