Submission #789489

#	Time	Username	Problem	Language	Result	Execution time	Memory
789489		Warinchai	Feast (NOI19_feast)	C++14	18 / 100	53 ms	8024 KiB

feast

#include<bits/stdc++.h>
using namespace std;
long long ar[300005];
long long sum[300005];
long long n,k;
pair<long long,int> solve(long long l){
    pair<long long,int>dp={0,0},best={0,0};
    for(int i=1;i<=n;i++){
        dp=max(dp,{sum[i]-l+best.first,best.second-1});
        best=max(best,{dp.first-sum[i],dp.second});
    }
    dp.second*=-1;
    return dp;
}
int main(){
    ios_base::sync_with_stdio(false);
    cin.tie(0);
    cin>>n>>k;
    long long sm=0;
    for(int i=1;i<=n;i++){
        cin>>ar[i];
        sm+=ar[i];
        sum[i]=sm;
    }
    long long st=0,en=3e14+1;
    while(st<en){
        long long m=(st+en)/2;
        pair<long long,int>tmp=solve(m);
        //cout<<m<<" "<<tmp.first<<" "<<tmp.second<<endl;
        if(tmp.second==k){
            cout<<tmp.first+m*k;
            return 0;
        }else if(tmp.second<k){
            en=m-1;
        }else{
            st=m+1;
        }
    }
}

• 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