Submission #726291

#	Time	Username	Problem	Language	Result	Execution time	Memory
726291		alvingogo	Rectangles (IOI19_rect)	C++14	72 / 100	5099 ms	493880 KiB

rect

#include "rect.h"
#include <bits/stdc++.h>
#pragma GCC optimize("Ofast,unroll-loops,inline")
#pragma GCC target("sse,sse2,ssse3,sse4,popcnt,abm,mmx,avx,tune=native")
#define fs first
#define sc second
using namespace std;

typedef pair<int,int> pii;

namespace{

struct BIT{
	int n;
	vector<int> bt;
	BIT(int x){
		n=x;
		bt.resize(x+1);
	}
	BIT(){
		n=0;
	}
	void update(int x,int y){
		for(;x<=n;x+=(x&-x)){
			bt[x]+=y;
		}
	}
	int query(int x){
		int ans=0;
		for(;x>0;x-=(x&-x)){
			ans+=bt[x];
		}
		return ans;
	}
};

}
long long count_rectangles(vector<vector<int> > v) {
	int n=v.size();
	int m=v[0].size();
	vector<vector<int> > tmp(m,vector<int>(n));
	for(int i=0;i<n;i++){
		for(int j=0;j<m;j++){
			tmp[j][i]=v[i][j];
		}
	}
	if(n<=2 || m<=2){
		return 0;
	}
	// swap(n,m);
	// v=tmp;
	vector<vector<pii> > az(n),bz(m);
	vector<pii> t1,t2;
	for(int i=1;i<n-1;i++){
		vector<pair<int,int> > gg;
		vector<int> vis(m),up(m),down(m);
		for(int j=0;j<m;j++){
			gg.push_back({v[i][j],j});
		}
		sort(gg.begin(),gg.end());
		for(auto h:gg){
			int x=h.sc-1,y=h.sc+1;
			int l=h.sc,r=h.sc;
			if(x<0 || !vis[x]){

			}
			else{
				l=up[x];
			}
			if(y>=m || !vis[y]){
				
			}
			else{
				r=down[y];
			}
			vis[h.sc]=1;
			up[h.sc]=l;
			down[h.sc]=r;
			down[l]=r;
			up[r]=l;
			if(l!=0 && r!=m-1 && (v[i][r+1]>h.fs && v[i][l-1]>h.fs)){
				az[i].push_back({l,r});
				t1.push_back({l,r});
			}
		}
	}
	for(int i=1;i<m-1;i++){
		vector<pair<int,int> > gg;
		vector<int> vis(n),up(n),down(n);
		for(int j=0;j<n;j++){
			gg.push_back({v[j][i],j});
		}
		sort(gg.begin(),gg.end());
		for(auto h:gg){
			int x=h.sc-1,y=h.sc+1;
			int l=h.sc,r=h.sc;
			if(x<0 || !vis[x]){

			}
			else{
				l=up[x];
			}
			if(y>=n || !vis[y]){
				
			}
			else{
				r=down[y];
			}
			vis[h.sc]=1;
			up[h.sc]=l;
			down[h.sc]=r;
			down[l]=r;
			up[r]=l;
			if(l!=0 && r!=n-1 && (v[r+1][i]>h.fs && v[l-1][i]>h.fs)){
				bz[i].push_back({l,r});
				t2.push_back({l,r});
			}
		}
	}
	sort(t1.begin(),t1.end());
	t1.erase(unique(t1.begin(),t1.end()),t1.end());
	sort(t2.begin(),t2.end());
	t2.erase(unique(t2.begin(),t2.end()),t2.end());
	auto lis1=[&](pii a){
		return lower_bound(t1.begin(),t1.end(),a)-t1.begin();
	};
	auto lis2=[&](pii a){
		return lower_bound(t2.begin(),t2.end(),a)-t2.begin();
	};
	vector<pair<int,pii> > ev[2505];
	vector<vector<int> > ax(n),bx(m);
	for(int i=1;i<n-1;i++){
		for(auto h:az[i]){
			ax[i].push_back(lis1(h));
		}
	}
	for(int i=1;i<m-1;i++){
		for(auto h:bz[i]){
			bx[i].push_back(lis2(h));
		}
	}
	vector<int> y1(t1.size(),-1),y2(t2.size(),-1),p1(t1.size()),p2(t2.size());
	for(int i=1;i<n-1;i++){
		for(auto h:ax[i]){
			p1[h]=1;
			if(y1[h]==-1){
				y1[h]=i;
			}
		}
		if(i>1){
			for(auto h:ax[i-1]){
				if(p1[h]==0){
					ev[t1[h].fs].push_back({-t1[h].sc,{y1[h],i-1}});
					y1[h]=-1;
				}
			}
		}
		for(auto h:ax[i]){
			p1[h]=0;
		}
	}
	for(int i=0;i<t1.size();i++){
		if(y1[i]!=-1){
			ev[t1[i].fs].push_back({-t1[i].sc,{y1[i],n-2}});
		}
	}
	for(int i=1;i<m-1;i++){
		for(auto h:bx[i]){
			p2[h]=1;
			if(y2[h]==-1){
				y2[h]=i;
			}
		}
		if(i>1){
			for(auto h:bx[i-1]){
				if(p2[h]==0){
					for(int j=y2[h];j<=i-1;j++){
						ev[j].push_back({-(i-1),{-t2[h].fs,-t2[h].sc}});
					}
					y2[h]=-1;
				}
			}
		}
		for(auto h:bx[i]){
			p2[h]=0;
		}
	}
	for(int i=0;i<y2.size();i++){
		if(y2[i]==-1){
			continue;
		}
		for(int j=y2[i];j<=m-2;j++){
			ev[j].push_back({-(m-2),{-t2[i].fs,-t2[i].sc}});
		}
	}
	// BIT vb[2502];
	// for(int i=0;i<n;i++){
	// 	vb[i]=BIT(n);
	// }
	vector<BIT> vb(n,BIT(n));
	long long ans=0;
	
	// for(int i=1;i<m-1;i++){
	// 	sort(ev[i].begin(),ev[i].end());
	// }
	for(int i=1;i<m-1;i++){
		sort(ev[i].begin(),ev[i].end());
		for(auto h:ev[i]){
			if(h.sc.sc>0){
				for(int j=h.sc.fs;j<=h.sc.sc;j++){
					ans+=vb[j].query(h.sc.sc);
				}	
			}
			else{
				vb[-h.sc.fs].update(-h.sc.sc,1);
			}
		}
		for(auto h:ev[i]){
			if(h.sc.sc<0){
				vb[-h.sc.fs].update(-h.sc.sc,-1);
			}
		}
	}
	return ans;
}

Compilation message (stderr)

rect.cpp: In function 'long long int count_rectangles(std::vector<std::vector<int> >)':
rect.cpp:162:15: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  162 |  for(int i=0;i<t1.size();i++){
      |              ~^~~~~~~~~~
rect.cpp:188:15: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  188 |  for(int i=0;i<y2.size();i++){
      |              ~^~~~~~~~~~

• Subtask 1: 8 / 8
• Subtask 2: 7 / 7
• Subtask 3: 12 / 12
• Subtask 4: 22 / 22
• Subtask 5: 10 / 10
• Subtask 6: 13 / 13
• Subtask 7: 0 / 28