제출 #1157368

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
1157368		elotelo966	Group Photo (JOI21_ho_t3)	C++20	100 / 100	3857 ms	265360 KiB

Main

#include <bits/stdc++.h>
using namespace std;
 
//#define int long long
#define faster ios_base::sync_with_stdio(false);cin.tie(NULL);cout.tie(NULL);
#define FOR for(int i=1;i<=n;i++)
#define lim 5005
#define mid (start+end)/2
#define pb push_back

vector<int> buy[lim];

int n;

int dizi[lim],mp[lim];

int duz[lim][lim],ters[lim][lim];

int dp[lim];

int tree[4*lim];

inline int query(int node,int start,int end,int l,int r){
	if(start>end || start>r || end<l)return 0;
	if(start>=l && end<=r)return tree[node];
	return query(node*2,start,mid,l,r)+query(node*2+1,mid+1,end,l,r);
}

inline void update(int node,int start,int end,int l,int r,int val){
	if(start>end || start>r || end<l)return ;
	if(start>=l && end<=r){
		tree[node]+=val;
		return ;
	}
	update(node*2,start,mid,l,r,val),update(node*2+1,mid+1,end,l,r,val);
	tree[node]=tree[node*2]+tree[node*2+1];
}

inline void build(int node,int start,int end){
	tree[node]=0;
	if(start==end)return ;
	build(node*2,start,mid),build(node*2+1,mid+1,end);
}

inline int f(int sira){
	if(sira>n)return 0;
	if(~dp[sira])return dp[sira];
	int cev=INT_MAX;
	for(int i=sira;i<=n;i++){
		cev=min(cev,f(i+1)+duz[sira][i]);
		cev=min(cev,f(i+1)+ters[sira][i]);
	}
	return dp[sira]=cev;
}

int main(){
	faster
	cin>>n;
	
	FOR{
		dp[i]=-1;
		cin>>dizi[i];
		mp[dizi[i]]=i;
	}
	
	FOR{
		int tut=query(1,1,n,dizi[i],n);
		for(int j=1;j<=dizi[i];j++){
			duz[j][dizi[i]]+=tut;
		}
		update(1,1,n,dizi[i],dizi[i],1);
	}
	
	FOR{
		for(int j=1;j<=n;j++){
			duz[i][j]+=duz[i][j-1];
			//cout<<duz[i][j]<<" ";
		}
		//cout<<'\n';
	}
	
	
	build(1,1,n);
	
	FOR{
		update(1,1,n,dizi[i],dizi[i],i-1);
	}
	
	FOR{
		for(int j=1;j<i;j++){
			if(dizi[j]>dizi[i]){
				buy[dizi[i]].pb(dizi[j]);
				update(1,1,n,dizi[j],dizi[j],-1);
			}
		}
	}
	
	FOR{
		for(int j=1;j<=n;j++){
			ters[i][j]=query(1,1,n,1,j);
		}
		update(1,1,n,i,i,-(mp[i]-1));
		for(auto a:buy[i]){
			update(1,1,n,a,a,1);
		}
		for(int j=mp[i];j<=n;j++){
			if(dizi[j]>i){
				update(1,1,n,dizi[j],dizi[j],-1);
				buy[dizi[j]].pb(dizi[j]);
			}
		}
	}
	
	//~ FOR{
		//~ for(int j=1;j<=n;j++)cout<<ters[i][j]<<" ";
		//~ cout<<endl;
	//~ }
	
	cout<<f(1)<<'\n';
	
	return 0;
}

• Subtask 1: 5 / 5
• Subtask 2: 7 / 7
• Subtask 3: 32 / 32
• Subtask 4: 20 / 20
• Subtask 5: 36 / 36