Submission #224716

#	Time	Username	Problem	Language	Result	Execution time	Memory
224716		kshitij_sodani	Feast (NOI19_feast)	C++17	30 / 100	56 ms	2748 KiB

feast

#include <iostream>
#include <bits/stdc++.h>
using namespace std;
#define a first
#define b second
#define pb push_back
typedef long long  int llo;
llo mod=1000000007;

llo ma=0;

int main(){
	ios_base::sync_with_stdio(false);
	cin.tie(NULL);
	llo n,k;
	cin>>n>>k;
	llo it[n];
	for(llo i=0;i<n;i++){
		cin>>it[i];
	}
	if(k==1){
		llo su=0;
		for(llo i=0;i<n;i++){
			su+=it[i];
			su=max(su,(llo)0);
			ma=max(ma,su);
		}
		cout<<ma<<endl;
		return 0;
	}
	llo ind=0;
	vector<llo> aa;
	while(ind<n){
		if(it[ind]<0){
			llo su=0;
			while(ind<n){
				if(it[ind]>0){
					break;
				}
				su+=it[ind];
				ind+=1;
			}
			aa.pb(su);
		}
		if(it[ind]>=0){
			llo su=0;
			while(ind<n){
				if(it[ind]<0){
					break;
				}
				su+=it[ind];
				ind+=1;
			}
			aa.pb(su);
		}
	}
	set<pair<llo,llo>> ac;
	llo kk=0;
	llo ll=aa.size()-1;
	if(aa[0]<0){
		kk+=1;
	}
	if(aa[ll]<0){
		ll-=1;
	}
	llo le[aa.size()];
	llo re[aa.size()];

	llo tot=0;
	for(llo i=kk;i<=ll;i++){
		if(aa[i]>0){
			tot+=1;
		}
		if(i>kk and i<=ll){
			le[i]=i-1;
		}
		else{
			le[i]=-1;
		}
	}
	for(llo i=kk;i<=ll;i++){
		if(i>=kk and i<ll){
			re[i]=i+1;
		}
		else{
			re[i]=-1;
		}
	}

	for(llo i=kk;i<=ll;i++){
		ac.insert({abs(aa[i]),i});
	}
	int vis[aa.size()];
	for(int i=0;i<aa.size();i++){
		vis[i]=0;
	}
	while(tot>k){
		auto xx=ac.begin();
		llo ind=(*xx).b;
		ac.erase(xx);
		if(le[ind]!=-1){
			vis[le[ind]]=1;
			ac.erase({aa[le[ind]],le[ind]});
			aa[ind]+=aa[le[ind]];

			if(le[le[ind]]!=-1){
				re[le[le[ind]]]=ind;
				le[ind]=le[le[ind]];
			}
			else{
				le[ind]=-1;
			}
		}
		if(re[ind]!=-1){
			vis[re[ind]]=1;
			ac.erase({aa[re[ind]],re[ind]});
			aa[ind]+=aa[re[ind]];
			if(re[re[ind]]!=-1){
				le[re[re[ind]]]=ind;
				re[ind]=re[re[ind]];
			}
			else{
				re[ind]=-1;
			}
		}
		tot-=1;	
		ac.insert({abs(aa[ind]),ind});
	}

	for(llo i=kk;i<=ll;i++){
		if(aa[i]>0 and vis[i]==0){
			ma+=aa[i];
		}
	}
	cout<<ma<<endl;

	return 0;
}

Compilation message (stderr)

feast.cpp: In function 'int main()':
feast.cpp:94:15: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(int i=0;i<aa.size();i++){
              ~^~~~~~~~~~

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