Submission #421175

#	Time	Username	Problem	Language	Result	Execution time	Memory
421175		MohamedAhmed04	Rectangles (IOI19_rect)	C++14	72 / 100	3908 ms	1048580 KiB

rect

#include <bits/stdc++.h>
#include "rect.h"
//#include "grader.cpp"

using namespace std ;

#include <ext/pb_ds/tree_policy.hpp>
#include <ext/pb_ds/assoc_container.hpp>

using namespace __gnu_pbds ;

template<class T> using ordered_set = tree<T , null_type , less<T> , rb_tree_tag , tree_order_statistics_node_update> ;

const int MAX = 2501 ;

ordered_set<int>s[MAX][MAX] ;
set<int>candi[MAX] ;
stack<int>st[MAX] ;

int n , m ;

int calc(int i , int j , int i2 , int last)
{
	int j2 = j-1 ;
	i2++ ;
	if(j2 < 0 || i2 >= i)
		return 0ll ;
	return (s[i2][j2].order_of_key(last+2) - s[i2][j2].order_of_key(j+1)) ;
}

vector< vector<int> >a ;
vector<int>erased ;

void AddRow(int i)
{
	stack<int>st2 ;
	for(int j = m-1 ; j >= 0 ; --j)
	{
		while(st2.size() && a[i][j] > a[i][st2.top()])
			s[i][j].insert(st2.top()) , st2.pop() ;
		if(st2.size())
			s[i][j].insert(st2.top()) ;
		while(st2.size() && a[i][st2.top()] == a[i][j])
			st2.pop() ;
		st2.push(j) ;
	}
	if(!i)
		return ;
	for(int j = 0 ; j < m ; ++j)
	{
		erased.clear() ;
		for(auto &k : s[i-1][j])
		{
			if(s[i][j].find(k) == s[i][j].end())
				erased.push_back(k) ;
		}
		for(auto &k : erased)
		{
			for(int i2 = i-1 ; i2 >= 0 ; --i2)
			{
				if(s[i2][j].find(k) == s[i2][j].end())
					break ;
				s[i2][j].erase(k) ;
			}
		}
	}
}

long long count_rectangles(std::vector<std::vector<int> > v) 
{
	a = v ;
	n = a.size() , m = a[0].size() ;
	long long ans = 0 ;
	for(int i = 0 ; i < n ; ++i)
	{
		for(int j = 0 ; j < m ; ++j)
		{
			while(st[j].size() && a[i][j] > a[st[j].top()][j])
				candi[j].insert(st[j].top()) , st[j].pop() ;
			if(st[j].size())
				candi[j].insert(st[j].top()) ;
			while(st[j].size() && a[st[j].top()][j] == a[i][j])
				st[j].pop() ;
			st[j].push(i) ;
		}
		for(int j = 0 ; j < m ; ++j)
		{
			for(auto &i2 : candi[j])
			{
				int last = j ;
				for(int k = j ; k < m ; ++k)
				{
					if(candi[k].find(i2) == candi[k].end())
						break ;
					last = k ;
				}
				for(int k = j ; k <= last ; ++k)
				{
					ans += calc(i , k , i2 , last) ;
					if(k != j)
						candi[k].erase(i2) ;
				}
			}
			candi[j].clear() ;
		}
		AddRow(i) ;
	}
	return ans ;
}

• 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