Submission #857625

#	Time	Username	Problem	Language	Result	Execution time	Memory
857625		hungnt	Feast (NOI19_feast)	C++14	12 / 100	28 ms	5604 KiB

feast

#include<bits/stdc++.h>
using namespace std;

const int N = 300005;

int n, k;
int a[N];
long long dp[2003][2003][2];

void sub3()
{
    long long ans = 0, mx = 0, mn = 0, s = 0;
    for(int i = 1; i <= n; i++)
    {
        s += a[i];
        mx = max(mx, s);
        mn = min(mn, s);
        ans = max(ans, mx - mn);
    }
    cout << ans;
}

void sub6()
{
    long long ans=0;
    dp[0][0][1] = 0;
    dp[0][0][0] = 0;
    for(int i = 1; i <= n; i++)
    {
        dp[i][0][0] = 0;
        for(int j = 1; j <= k; j++)
        {
            dp[i][j][0] = max(dp[i - 1][j][1], dp[i - 1][j][0]);
            dp[i][j][1] = max(dp[i - 1][j][1], dp[i - 1][j - 1][0]) + a[i];
			ans = max({ans, dp[i][j][0], dp[i][j][1]});
        }
    }
    cout << ans;
}

int main()
{
    ios_base::sync_with_stdio(0);
    cin.tie(0); cout.tie(0);
    cin >> n >> k;
    int cntam = 0;
    long long s = 0;
    for(int i = 1; i <= n; i++)
    {
        cin >> a[i];
        cntam += (a[i] < 0);
    }
    if(k == 1)
    {
        sub3();
        return 0;
    }
    if(cntam <= 1)
    {
        long long ans = 0;
        for(int i = 1; i <= n; i++) if(a[i] > 0) ans += a[i];
        cout << ans;
        return 0;
    }
    sub6();
    return 0;
}

Compilation message (stderr)

feast.cpp: In function 'int main()':
feast.cpp:47:15: warning: unused variable 's' [-Wunused-variable]
   47 |     long long s = 0;
      |               ^

• 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