Submission #238535

#	Time	Username	Problem	Language	Result	Execution time	Memory
238535		Pbezz	Feast (NOI19_feast)	C++14	51 / 100	1089 ms	16768 KiB

feast

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

#define loop(i,n) for (ll i = 0; i < n; i++)

#define ll long long
#define INF 1e9+5
#define MAXN 300007
#define pb push_back 
#define mp make_pair
typedef pair<ll,ll> pii;

ll n,k;
vector<ll>dp(MAXN);//de 1 a n
ll arr[2005][2005][2];

ll siga(ll pos, ll left,bool maybe){
//retornar o best que posso fazer
//usei até pos-1

	if(pos==n+1)return 0;
	if(left==0)return 0;

	ll x;
	if(maybe)x=1;
	else x=0;

	if(arr[pos][left][x]!=-1){
	return arr[pos][left][x];
	}

	ll i,ret=0,k,gains;


	for(i=pos;i<=n;i++){//usar até i

	gains=dp[i]-dp[pos-1];

	k = siga(i+1,left-1,true)+gains;

	ret=max(ret,k);

	if(maybe){

	k = siga(i+1,left,false);
	ret=max(ret,k);
}

}
	arr[pos][left][x]=ret;
	return ret;

}


int main(){

	ios::sync_with_stdio(0);
	cin.tie(0);
	cout.tie(0);
 
	

	ll i,ans,count=0,mini,x;
	cin>>n>>k;

	vector<ll>a(n+1);

	for(i=1;i<=n;i++){
	cin>>a[i];

	if(a[i]<0){count++; mini=i;}

	dp[i]=dp[i-1]+a[i];

}

	if(count==0){
	ans=dp[n];
	}else if(count==1){

	if(k>=2)ans=dp[n]-a[mini];
	else{
	x=dp[n]-dp[mini];
	ans=max(dp[n], max(dp[mini-1], x));
	}

	}else if(k==1){//clássico maximum sum subarray

	ans=0;
	vector<ll>bruh(n+1);

	for(i=1;i<=n;i++){

	bruh[i]=max(bruh[i-1],(ll int)0)+a[i];
	ans=max(ans,bruh[i]);
}

	}else{//bruteforce básico
	ll j;
	for(i=0;i<=n+1;i++){
	for(j=0;j<=k+1;j++){
	arr[i][j][0]=(ll)-1;
	arr[i][j][1]=(ll)-1;
	}
}

	ans=siga(1,k,true);

}

	printf("%lld\n",ans);

return 0;
}

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