Submission #345557

#	Time	Username	Problem	Language	Result	Execution time	Memory
345557		Nursik	Feast (NOI19_feast)	C++14	12 / 100	136 ms	49260 KiB

feast

#include <bits/stdc++.h>

#define f first
#define s second
#define ll long long
#define pb push_back
#define all(v) v.begin(),v.end() 
#define ld long double

using namespace std; 
 
void data() {
	#ifdef NURS
        freopen("main.in", "r", stdin);
        freopen("main.out", "w", stdout);
    #endif	
} 
void win()
{	
	ios_base::sync_with_stdio(0),
	cin.tie(0),cout.tie(0);
}

int block = 400;
const ld eps = 1e-6; 

const int N = 1e6 + 500;
const int mod = 1e9 + 7;

const ll hh = 100010683;
const ll hh2 = 150005819;

int n, k, g, pos;
int a[N];
ll s, ans;
ll dp[5000][5000], pref[5000];
int main()
{
	data();              
	win();        
	cin >> n >> k;
	bool was = 0;
	for (int i = 1; i <= n; i++)
	{
		cin >> a[i];
		was = was | (a[i] < 0), s += a[i];
		if (a[i] < 0)
			g++, pos = i;
		pref[i] += pref[i - 1] + a[i];
	}
	//first subtask
	if (was == 0)
	{
		cout << s << '\n';
		return 0;
	}
	//second subtask
	if (g == 1 && k >= 2)
	{
		cout << s - a[pos] << '\n';
		return 0;	
	}
	else if (g == 1 && k == 1)
	{
		ans = max(ans, s);
		s = 0;
		for (int i = 1; i < pos; i++)
			s += a[i];
		ans = max(ans, s), s = 0;
		for (int i = pos + 1; i <= n; i++)
			s += a[i];
		ans = max(ans, s);
		cout << ans << '\n';
		return 0;
	}
	//3, 4, 5 subtasks
	for (int i = 0; i <= n; i++)
	{
		for (int j = 0; j <= k; j++)
		{
			dp[i][j] = -1e9;
		} 
	}
	dp[0][0] = 0;
	for (int i = 1; i <= n; i++)
	{
		for (int j = 1; j <= k; j++)
		{
			for (int len = 1; len <= i; len++)
			{
				if (dp[i - len][j - 1] != -1e9)
				{
					dp[i][j] = max(dp[i - len][j - 1] + pref[i] - pref[i - len], dp[i][j]); 
				}
			}
			dp[i][j] = max(dp[i][j], dp[i - 1][j]);
			if (i == n && j == k)
				ans = max(ans, dp[i][j]);
		}
		dp[i][0] = max(dp[i][0], dp[i - 1][0]);
	}
	cout << ans;
}

• Subtask 1: 4 / 4
• Subtask 2: 8 / 8
• Subtask 3: 0 / 18
• Subtask 4: 0 / 10
• Subtask 5: 0 / 11
• Subtask 6: 0 / 20
• Subtask 7: 0 / 29