Submission #523602

#	Time	Username	Problem	Language	Result	Execution time	Memory
523602		DanerZein	Discharging (NOI20_discharging)	C++14	0 / 100	365 ms	34556 KiB

Discharging

#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
const int MAX_N=1e6+10;
const int MAX_P=MAX_N*4;
const int MAX=1e9;
ll val[MAX_N];
int tr[MAX_P];
ll ma[MAX_N];
ll n;
void maxi(){
  int m=-1,id;
  for(int i=0;i<n;i++){
    if(m<val[i]){
      m=val[i];
      id=i;
    }
    ma[i]=id;
  }
}
ll dp[MAX_N];
ll maxres(int l,int r){
  if(dp[r]!=-1) return dp[r];
  int i=ma[r];
  if(i==0) return val[i]*n;
  ll d=(n-i);
  ll ans=val[i]*n;
  for(int k=i-1;k>=0;k--){
    
    ans=min(ans,val[i]*d+maxres(0,k));
    d++;
  }
  return dp[r]=ans;
}
ll mdp[MAX_N];
int coste(int i,int x){
  return x*(n+1)-i*x+mdp[i-1];
}
int time(int i,int j){
  int l=0,r=1e6+10;
  while(r-l>1){
    int mid=(l+r)/2;
    if(coste(i,mid)>=coste(j,mid)) r=mid;
    else l=mid;
  }
  return r;
}
int main(){
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  cout.tie(NULL);
  memset(dp,-1,sizeof dp);
  cin>>n;
  for(int i=0;i<n;i++){
    int a; cin>>a;
    val[i]=a;
  }
  mdp[0]=0;
  deque<int> dq;
  
  for(int i=1;i<=n;i++){
    mdp[i]=1e9;
    int t=dq.size();
    while(t>=3 && time(dq[t-2],dq[t-1])>=time(dq[t-2],i)){
      dq.pop_back(); t--;
    }
    dq.push_back(i);
    while(dq.size()>=2 && coste(dq[0],val[i-1])>=coste(dq[1],val[i-1])){
      dq.pop_front();
    }
    mdp[i]=coste(dq.front(),val[i-1]);
  }
  cout<<mdp[n]<<endl;
}

Compilation message (stderr)

Discharging.cpp: In function 'void maxi()':
Discharging.cpp:18:11: warning: 'id' may be used uninitialized in this function [-Wmaybe-uninitialized]
   18 |     ma[i]=id;
      |           ^~

• Subtask 1: 0 / 9
• Subtask 2: 0 / 13
• Subtask 3: 0 / 25
• Subtask 4: 0 / 11
• Subtask 5: 0 / 14
• Subtask 6: 0 / 28