Submission #731487

#	Time	Username	Problem	Language	Result	Execution time	Memory
731487		mohav48173	Feast (NOI19_feast)	C++14	18 / 100	203 ms	5040 KiB

feast

#include<bits/stdc++.h>
using namespace std;
int n,k;
long long a[400000];
long long m[400000];
long long mincnt=0;
long long score=0;
long long get(int ind) {
    if(ind<0)return 0;
    else return m[ind];
}
void calc(long long lam) {
    long long bestscore=0;
    long long bestcnt=0;
    long long bestnxt=-lam;
    long long nxtcnt=0;
    for(int i=0;i<n;i++) {
        if(bestscore-lam-get(i-1)>bestnxt ||
           (bestscore-lam-get(i-1)==bestnxt && nxtcnt>bestcnt)) {
            bestnxt=bestscore-get(i-1)-lam;
            nxtcnt=bestcnt;
        }
        if(bestnxt+get(i)>bestscore || (bestnxt+get(i)==bestscore && nxtcnt+1<bestcnt)) {
            bestscore=bestnxt+get(i);
            bestcnt=nxtcnt+1;
        }
    }
    mincnt=bestcnt;
    score=bestscore;
}
int main() {
    cin>>n>>k;
    for(int i=0;i<n;i++)cin>>a[i];
    m[0]=a[0];for(int i=1;i<n;i++)m[i]=m[i-1]+a[i];
    long long l=0,r=1e17;
    while(l+1<r) {
        long long mid=(l+r)/2;
        calc(mid);
        if(mincnt<=k)r=mid;
        else l=mid;
    }
    calc(r);
    cout<<score+k*r<<endl;
    return 0;
}

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