Submission #1175387

#	Time	Username	Problem	Language	Result	Execution time	Memory
1175387		sasde	Feast (NOI19_feast)	C++20	100 / 100	103 ms	12192 KiB

feast

#include<bits/stdc++.h>
#define int long long 
#define task "strdel"
#define ii pair<int,int>
#define iii pair<int,ii>
#define iv pair<ii,ii>
#define se second
#define fi first
#define ffi fi.fi
#define sfi se.fi
#define sse se.se
#define fse fi.se
#define lt(i, c, d) for(int i = c; i <= d; ++i)
#define fl(i, c, d) for(int i = d; i >= c; --i)
#define pb push_back
#define emb emplace_back
#define emf emplace_front
#define em emplace
using namespace std;
const int N=1e6+5,lg=20,mod=1e9+7;
mt19937 rd(chrono::steady_clock::now().time_since_epoch().count());
int Rand(int u,int v){
 return u+rd()%(v-u+1);
}
ii dp[N][2];
int n,a[N],k;
ii check(int mid){
  dp[1][0]={0,0};
  dp[1][1]={a[1]-mid,1};
  for(int i=2;i<=n;++i){
    dp[i][0]=max(dp[i-1][0],dp[i-1][1]);
    ii u={dp[i-1][0].fi+a[i]-mid,dp[i-1][0].se+1};
    ii v={dp[i-1][1].fi+a[i],dp[i-1][1].se};
    dp[i][1]=max(u,v);
  }
  return max(dp[n][0],dp[n][1]);
}
void solve(){
  cin >> n >> k;
  for(int i=1;i<=n;++i)cin >> a[i];
    int r=0,l=0,res=0;
  for(int i=1;i<=n;++i)l=max(l,a[i]*n);
  while(r<=l){
    int mid=(r+l)>>1;
    if(check(mid).se>=k){
      res=mid;
      r=mid+1;
    }
    else l=mid-1;

  }
  cout <<check(res).fi+k*res;
}
main()
{
  srand(time(0));
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    cout.tie(NULL);
    if(fopen(task".inp","r")){
      freopen(task".inp","r",stdin);
      freopen(task".out","w",stdout);
    }
    int t=1;
 //   cin >> t;
while(t--){
    solve();
    cout<<'\n';
}

}

Compilation message (stderr)

feast.cpp:54:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
   54 | main()
      | ^~~~
feast.cpp: In function 'int main()':
feast.cpp:61:14: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   61 |       freopen(task".inp","r",stdin);
      |       ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~
feast.cpp:62:14: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   62 |       freopen(task".out","w",stdout);
      |       ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~

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