Submission #291666

#	Time	Username	Problem	Language	Result	Execution time	Memory
291666		pit4h	Rectangles (IOI19_rect)	C++14	72 / 100	5106 ms	643844 KiB

rect

#include "rect.h"
#include <bits/stdc++.h>
#define ll long long
#define st first
#define nd second
#define mp make_pair
using namespace std;
using vec2d = vector<vector<pair<int, int>>>;
int n, m;
struct Segment {
	int l, r, h;
};
ll count_rectangles(vector<vector<int>> a) {
	n = a.size();
	m = a[0].size();
	vector<vec2d> horiz(n, vec2d(m));
	for(int i=0; i<n; ++i) {
		vector<int> mono;
		for(int j=0; j<m; ++j) {
			while(mono.size() && a[i][mono.back()] < a[i][j]) {
				if(mono.back()+1 <= j-1) {
					horiz[i][mono.back()+1].push_back(mp(j-1, 1));
				}
				mono.pop_back();
			}
			if(mono.size() && mono.back()+1 <= j-1) {
				horiz[i][mono.back()+1].push_back(mp(j-1, 1));	
			}
			if(mono.size() && a[i][mono.back()] == a[i][j]) {
				mono.pop_back();
			}
			mono.push_back(j);
		}
		if(i!=0) {
			for(int j=0; j<m; ++j) {
				int k = 0;
				for(auto &it: horiz[i][j]) {
					while(k<(int)horiz[i-1][j].size() && horiz[i-1][j][k].st < it.st) {
						k++;
					}
					if(k<(int)horiz[i-1][j].size() && horiz[i-1][j][k].st == it.st) {
						it.nd = horiz[i-1][j][k].nd + 1;
					}
				}
			}
		}
	}
	vector<vector<Segment>> segh(m);
	for(int i=0; i<n; ++i) {
		if(i < n-1) {
			for(int j=0; j<m; ++j) {
				int k = 0;
				for(auto it: horiz[i][j]) {
					while(k<(int)horiz[i+1][j].size() && horiz[i+1][j][k].st < it.st) {
						k++;
					}
					if(k==(int)horiz[i+1][j].size() || horiz[i+1][j][k].st != it.st) {
						segh[j].push_back({i-it.nd+1, i, it.st-j+1});
					}
				}
			}
		}
		else {
			for(int j=0; j<m; ++j) {
				for(auto it: horiz[i][j]) {
					segh[j].push_back({i-it.nd+1, i, it.st-j+1});
				}
			}
		}
	}
	/// **************************************
	/// *** horizontal segments calculated ***
	/// **************************************
	vector<vec2d> vert(m, vec2d(n));
	for(int j=m-1; j>=0; --j) {
		vector<int> mono;
		for(int i=0; i<n; ++i) {
			while(mono.size() && a[mono.back()][j] < a[i][j]) {
				if(mono.back()+1 <= i-1) {
					vert[j][mono.back()+1].push_back(mp(i-1, 1));
				}
				mono.pop_back();
			}
			if(mono.size() && mono.back()+1 <= i-1) {
				vert[j][mono.back()+1].push_back(mp(i-1, 1));
			}
			if(mono.size() && a[mono.back()][j] == a[i][j]) {
				mono.pop_back();
			}
			mono.push_back(i);
		}
		if(j < m-1) {
			for(int i=0; i<n; ++i) {
				int k = 0;
				for(auto &it: vert[j][i]) {
					while(k<(int)vert[j+1][i].size() && vert[j+1][i][k].st < it.st) {
						k++;
					}
					if(k<(int)vert[j+1][i].size() && vert[j+1][i][k].st == it.st) {
						it.nd = vert[j+1][i][k].nd + 1;
					}
				}
			}
		}
	}

	vector<vector<Segment>> segv(m);
	for(int j=m-1; j>=0; --j) {
		/*if(j > 0) {
			for(int i=0; i<n; ++i) {
				int k = 0;
				for(auto it: vert[j][i]) {
					while(k<(int)vert[j-1][i].size() && vert[j-1][i][k].st < it.st) {
						k++;
					}
					if(k==(int)vert[j-1][i].size() || vert[j-1][i][k].st != it.st) {
						segv[j].push_back({i, it.st, it.nd});
					}
				}
			}
		}*/
		for(int i=0; i<n; ++i) {
			for(auto it: vert[j][i]) {
				segv[j].push_back({i, it.st, it.nd});
			}
		}
	}
	ll ans = 0;
	for(int col=0; col<m; ++col) {
		//cerr<<"col: "<<col<<'\n';
		for(auto it: segh[col]) {
			//cerr<<it.l<<' '<<it.r<<' '<<it.h<<'\n';	
			int cnt = 0;
			for(auto i: segv[col]) {
				if(i.h >= it.h && i.l >= it.l && i.r <= it.r) {
					cnt++;
				}
			}
			ans += cnt;
		}
	}
	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