Submission #949039

#	Time	Username	Problem	Language	Result	Execution time	Memory
949039		alexdd	Feast (NOI19_feast)	C++17	0 / 100	351 ms	12756 KiB

feast

#include<bits/stdc++.h>
using namespace std;
#define int long long
typedef long double ld;
const int INF = 1e9;
int n,k;
int a[300005];
int dp[300005];
int cnt[300005];
int pref[300005];
ld coef;
void solve()
{
    int mxm=0,cate=0;
    for(int i=1;i<=n;i++)
    {
        pref[i] = pref[i-1] + a[i];

        dp[i] = dp[i-1];
        cnt[i] = cnt[i-1];

        int aux = mxm + pref[i] - coef;
        if(aux>dp[i] || (aux==dp[i] && cate+1<cnt[i]))
        {
            dp[i] = aux;
            cnt[i] = cate+1;
        }
        if(dp[i]-pref[i]>mxm || (dp[i]-pref[i]==mxm && cate<cnt[i]))
        {
            mxm = dp[i]-pref[i];
            cate = cnt[i];
        }
    }
}
/**

dp[i] = max(dp[x] - pref[x]) + pref[i] - coef

*/
signed main()
{
    cin>>n>>k;
    for(int i=1;i<=n;i++)
        cin>>a[i];
    ld st,dr;
    st=-INF;
    dr=INF;
    for(int it=0;it<100;it++)
    {
        coef = (st+dr)/2.0;
        solve();
        if(cnt[n]>=k)
            st=coef;
        else
            dr=coef;
    }
    cout<<max((int)0,(int)(dp[n] + cnt[n]*coef));
    //cout<<dp[n] + k*coef;
    return 0;
}

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