Submission #791334

#	Time	Username	Problem	Language	Result	Execution time	Memory
791334		trucmai	Feast (NOI19_feast)	C++17	41 / 100	68 ms	65768 KiB

feast

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

#ifdef LOCAL
	#include "/home/trucmai/.vim/tools.h"
	#define debug(x...) cerr << "\e[91m"<<__func__<<":"<<__LINE__<<" [" << #x << "] = ["; _print(x); cerr << "\e[39m" << endl;
	#else
	#define debug(x...)
#endif

void open(){
  if(fopen("i.inp","r")){
    freopen("i.inp","r",stdin);
    freopen("o.out","w",stdout);
  }
}

#define ll long long
#define all(a) (a).begin(), (a).end()
#define vi vector<ll>
#define pi pair<ll,ll>
#define pii pair<ll,pair<ll,ll>>
#define fi first
#define se second
#define gcd __gcd
#define mset(a,v) memset(a, v, sizeof(a))
#define endl '\n'
#define spc " "

const int MN1 = 1e6 + 5,MN2 = 2e3 + 5,LOG = 27;
const ll MOD = 1e9 + 7,INF = 1e9;
ll n,k,a[MN1],dp[MN2][MN2][2];
/*
dp[i][j][k(0\1)] la max sum tai vi tri i,segment j va state k 
k = 0: 
  dp[i][j][0] = max(dp[i-1][j][0],dp[i-1][j][1] + a[j])
k = 1:
  dp[i][j][1] = max(dp[i-1][j-1][0],dp[i-1][j][1] + a[j])
*/
void solve(){
  cin>>n>>k;
  for(ll i = 1;i <= n;++i) cin>>a[i];
  mset(dp,-1);
  auto f=[&](ll i,ll j,bool state,auto &&f)->ll{
    if(i > n || j > k) return 0;
    ll &res = dp[i][j][state]; 
    if(res != -1) return res;
    res = 0; 
    res = max(res,f(i+1,j,1,f) + a[i]);
    if(!state) res = max(res,f(i+1,j,0,f));
    else if(j + 1 < k && state) res = max(res,f(i+1,j+1,0,f)); 
    return res;
  };
  cout<<f(1,0,0,f)<<endl;
}

signed main(){
  cin.tie(0) -> sync_with_stdio(0);
  open();
  ll t = 1; //cin>>t;
  while(t--) solve(); 
  
  #ifdef LOCAL
    cerr << endl << "Time elapsed: " << 1.0 * clock() / CLOCKS_PER_SEC << " s.\n";
  #endif
}

Compilation message (stderr)

feast.cpp: In function 'void open()':
feast.cpp:14:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   14 |     freopen("i.inp","r",stdin);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~
feast.cpp:15:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   15 |     freopen("o.out","w",stdout);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~

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