Submission #1159257

#	Time	Username	Problem	Language	Result	Execution time	Memory
1159257		Der_Vlapos	Monochrome Points (JOI20_monochrome)	C++20	25 / 100	2095 ms	328 KiB

monochrome

#include <bits/stdc++.h>

using namespace std;

#define ll long long
#define pb push_back
#define pii pair<int, int>
#define f first
#define s second
#define all(v) v.begin(), v.end()

// #define int ll

const int mod1 = 1e9 + 7;
const int mod2 = 998244353;

int dp1[1003][1003];
int dp2[1003][1003];

struct test
{
	void solve()
	{
		int n;
		cin >> n;
		vector<int> b, w;
		for (int i = 0; i < 2 * n; ++i)
		{
			char x;
			cin >> x;
			if (x == 'B')
				b.pb(i);
			else
				w.pb(i);
		}
		int res = 0;
		for (int k = 0; k < n; ++k)
		{
			vector<pii> segs;
			for (int i = 0; i < n; ++i)
				segs.pb({min(b[i], w[(i + k) % n]), max(b[i], w[(i + k) % n])});

			sort(all(segs));
			int cnt = 0;
			for (int i = 0; i < n; ++i)
				for (int j = i + 1; j < n; ++j)
				{
					cnt += (segs[j].f < segs[i].s and segs[i].s < segs[j].s);
				}
			res = max(res, cnt);
		}

		cout << res << "\n";
	}
};

main()
{
	test t;
	t.solve();
}

Compilation message (stderr)

monochrome.cpp:57:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
   57 | main()
      | ^~~~

• Subtask 1: 4 / 4
• Subtask 2: 21 / 21
• Subtask 3: 0 / 10
• Subtask 4: 0 / 65