Submission #833260

#	Time	Username	Problem	Language	Result	Execution time	Memory
833260		kwongweng	Feast (NOI19_feast)	C++17	59 / 100	109 ms	262144 KiB

feast

#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef vector<int> vi;
typedef pair<int, int> ii;
typedef vector<ii> vii;
typedef long double ld;
typedef pair<ll, ll> pll;
#define FOR(i, a, b) for(int i = a; i < b; i++)
#define ROF(i, a, b) for(int i = a; i >= b; i--)
#define ms memset
#define pb push_back
#define fi first
#define se second

const ll INF = 1e18;

void solve(){
  int n,k; cin>>n>>k;
  vi a(n+1); FOR(i,1,n+1) cin>>a[i];
  vector<ll> s(n+1); FOR(i,1,n+1) s[i]=s[i-1]+a[i];
  ll dp[n+1][k+1]; ms(dp,0,sizeof(dp));
  ll f[n+1][k+1]; ms(f,0,sizeof(f));
  FOR(i,1,n+1){
    f[i][0]=-s[i];
    f[i][0]=max(f[i][0],f[i-1][0]);
    FOR(j,1,k+1){
      dp[i][j]=max(dp[i][j],dp[i][j-1]);
      dp[i][j]=max(dp[i][j],dp[i-1][j]);
      dp[i][j]=max(dp[i][j],s[i]+f[i-1][j-1]);
      f[i][j]=dp[i][j]-s[i];
      if (i>1) f[i][j]=max(f[i][j],f[i-1][j]);
      //cout<<dp[i][j]<<" ";
      //cout<<f[i][j]<<" ";
    }
    //cout<<"\n";
  }
  cout<<dp[n][k]<<"\n";
}

int main(){
	//MOD=MOD1;
    ios::sync_with_stdio(false);
    if (fopen("input.txt", "r")) {
		  freopen("input.txt", "r", stdin);
    	freopen("output.txt", "w", stdout);
	  }
    int TC = 1;
    //cin >> TC; 
    FOR(i, 1, TC+1){
        //cout << "Case #" << i << ": ";
        solve();
    }
	
	return 0;
}

Compilation message (stderr)

feast.cpp: In function 'int main()':
feast.cpp:45:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   45 |     freopen("input.txt", "r", stdin);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
feast.cpp:46:13: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   46 |      freopen("output.txt", "w", stdout);
      |      ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~

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