Submission #119980

#	Time	Username	Problem	Language	Result	Execution time	Memory
119980		tutis	Growing Vegetable is Fun 3 (JOI19_ho_t3)	C++17	15 / 100	11 ms	3200 KiB

joi2019_ho_t3

/*input
20
YYGYYYGGGGRGYYGRGRYG
*/
#pragma GCC optimize ("O3")
#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef long double ld;
unordered_map<bitset<1202>, int>M;
int dp(bitset<1202>s, int x, int n)
{
	s[1200] = x % 2;
	s[1201] = x / 2;
	if (n == 1)
	{
		if (s[x * 400])
			return 0;
		else
			return 3e8;
	}
	if (M.count(s))
		return M[s];
	for (int i = n - 1; i >= 0; i--)
	{
		if (s[x * 400 + i])
		{
			bitset<1202>ss = s;
			ss[x * 400 + i] = 0;
			for (int j = i; j + 1 < n; j++)
			{
				ss[j] = ss[j + 1];
				ss[400 + j] = ss[400 + j + 1];
				ss[800 + j] = ss[800 + j + 1];
			}
			int cost = (n - 1) - i;
			int mini = 3e8;
			for (int y = 0; y < 3; y++)
			{
				if (x != y)
				{
					mini = min(mini, dp(ss, y, n - 1));
				}
			}
			return M[s] = cost + mini;
		}
	}
	return M[s] = 3e8;
}
int main()
{
	ios_base::sync_with_stdio(false);
	int n;
	string s;
	cin >> n >> s;
	bitset<1202>ss;
	for (int i = 0; i < n; i++)
	{
		if (s[i] == 'R')
			ss[i] = true;
		if (s[i] == 'G')
			ss[400 + i] = true;
		if (s[i] == 'Y')
			ss[800 + i] = true;
	}
	int ans = min({dp(ss, 0, n), dp(ss, 1, n), dp(ss, 2, n)});
	if (ans > 1e8)
		ans = -1;
	cout << ans << "\n";
}

• Subtask 1: 0 / 5
• Subtask 2: 0 / 55
• Subtask 3: 15 / 15
• Subtask 4: 0 / 25