Submission #132942

#	Time	Username	Problem	Language	Result	Execution time	Memory
132942		Mahmoud_Adel	Linear Garden (IOI08_linear_garden)	C++14	100 / 100	268 ms	3376 KiB

linear_garden

#include <bits/stdc++.h>
using namespace std;
#define f first
#define s second
typedef long long ll;
const int N = 1e6+5;
int n, mod;
ll dp[2][2][3][3];
string s;
ll sol(int i, int bit, int l, int p)
{
	return dp[i%2][bit][l][p];
}
ll solve()
{
	//~ if(i == n) return 1;
	//~ ll &ret = dp[i][bit][l][p];
	//~ if(ret != -1) return ret;
	//~ ret = 0;
	//~ if(bit)
	//~ {
		//~ if(l < 2) ret += sol(i+1, bit, l+1, max(0, p-1));
		//~ if(p < 2) ret += sol(i+1, bit, max(l-1, 0), p+1), ret %= mod;
	//~ }
	//~ else
	//~ {
		//~ if(s[i] == 'L') ret += sol(i+1, bit, l+1, max(p-1, 0));
		//~ else
		//~ {
			//~ if(l < 2) ret += sol(i+1, 1, l+1, max(p-1, 0));
			//~ ret += sol(i+1, 0, max(0, l-1), p+1), ret %= mod;
		//~ }
	//~ } 
	//~ return ret;
	for(int i=0; i<2; i++) for(int j=0; j<3; j++) for(int k=0; k<3; k++) dp[n%2][i][j][k] = 1;
	for(int i=n-1; i>=0; i--)
	{
		for(int bit=0; bit<2; bit++)
		{
			for(int l=0; l<3; l++)
			{
				for(int p=0; p<3; p++)
				{
					ll &ret = dp[i%2][bit][l][p];
					ret = 0;
					if(bit)
					{
						if(l < 2) ret += sol(i+1, bit, l+1, max(0, p-1));
						if(p < 2) ret += sol(i+1, bit, max(l-1, 0), p+1), ret %= mod;
					}
					else
					{
						if(s[i] == 'L') ret += sol(i+1, bit, l+1, max(p-1, 0));
						else
						{
							if(l < 2) ret += sol(i+1, 1, l+1, max(p-1, 0));
							ret += sol(i+1, 0, max(0, l-1), p+1), ret %= mod;
						}
					}
				}
			}
		}
	}
	return dp[0][0][0][0];
}
int main()
{
	memset(dp, -1, sizeof dp);
	cin >> n >> mod >> s;
	cout << solve() << endl;
}

• Subtask 1: 2 / 2
• Subtask 2: 2 / 2
• Subtask 3: 4 / 4
• Subtask 4: 4 / 4
• Subtask 5: 4 / 4
• Subtask 6: 4 / 4
• Subtask 7: 4 / 4
• Subtask 8: 4 / 4
• Subtask 9: 4 / 4
• Subtask 10: 4 / 4
• Subtask 11: 4 / 4
• Subtask 12: 5 / 5
• Subtask 13: 5 / 5
• Subtask 14: 5 / 5
• Subtask 15: 5 / 5
• Subtask 16: 5 / 5
• Subtask 17: 5 / 5
• Subtask 18: 5 / 5
• Subtask 19: 5 / 5
• Subtask 20: 5 / 5
• Subtask 21: 5 / 5
• Subtask 22: 5 / 5
• Subtask 23: 5 / 5