Submission #583552

#	Time	Username	Problem	Language	Result	Execution time	Memory
583552		Lucpp	Rectangles (IOI19_rect)	C++17	72 / 100	5121 ms	638476 KiB

rect

#include "rect.h"
#include <bits/stdc++.h>
using namespace std;
#define sz(x) ((int)(x).size())
 
vector<int> fen;
void add(int i, int x){
	for(i++; i < sz(fen); i+=i&-i) fen[i] += x;
}
int qry(int i){
	int ans = 0;
	for(i++; i > 0; i-=i&-i) ans += fen[i];
	return ans;
}
int qry(int i, int j){
	if(i > 0) return qry(j)-qry(i-1);
	else return qry(j);
}
 
long long count_rectangles(vector<vector<int>> a) {
	int n = sz(a), m = sz(a[0]);
	vector<vector<int>> r1(n, vector<int>(m, -1)), r2(n, vector<int>(m, -1));
	for(int i = 1; i < n-1; i++){
		stack<pair<int, int>> st({{a[i][0], 0}});
		for(int j = 1; j < m; j++){
			while(!st.empty() && a[i][j] > st.top().first){
				auto [h, k] = st.top();
				st.pop();
				r2[i][k] = j-1;
			}
			if(!st.empty()) {
				if(st.top().first > a[i][j]) r1[i][j] = st.top().second+1;
				else r1[i][j] = r1[i][st.top().second];
			}
			st.emplace(a[i][j], j);
		}
	}
	vector<vector<int>> c1(n, vector<int>(m, -1)), c2(n, vector<int>(m, -1));
	for(int j = 1; j < m-1; j++){
		stack<pair<int, int>> st({{a[0][j], 0}});
		for(int i = 1; i < n; i++){
			while(!st.empty() && a[i][j] > st.top().first){
				auto [h, k] = st.top(); st.pop();
				c2[k][j] = i-1;
			}
			if(!st.empty()){
				if(st.top().first > a[i][j]) c1[i][j] = st.top().second+1;
				else c1[i][j] = c1[st.top().second][j];
			}
			st.emplace(a[i][j], i);
		}
	}
	int mx = max(n, m);
	fen.resize(mx+1);
	vector<bool> valid;
	unordered_set<long long> noDupl;
	unordered_map<int, vector<tuple<short, short, int>>> byI, byJ;
	unordered_map<int, vector<short>> goodI, goodJ;
	int q = 0;
	for(int i = 1; i < n-1; i++){
		for(int j = 1; j < m-1; j++){
			// cerr << "\n" << i << " " << j << " " << r1[i][j] << " " << r2[i][j] << " " << c1[i][j] << " " << c2[i][j] << "\n";
			if(r1[i][j] != -1 && r2[i][j] != -1 && c1[i][j] != -1 && c2[i][j] != -1){
				int x = c1[i][j]*mx + c2[i][j], y = r1[i][j]*mx + r2[i][j];
				goodJ[x].push_back(j);
				goodI[y].push_back(i);
				long long t = (long long)x*(mx*mx)+y;
				if(noDupl.count(t)) continue;
				noDupl.insert(t);
				valid.push_back(true);
				byI[x].emplace_back(r1[i][j], r2[i][j], q);
				byJ[y].emplace_back(c1[i][j], c2[i][j], q);
				q++;
			}
		}
	}
	for(const auto& [id, v] : byI){
		int last = -1;
		sort(goodJ[id].begin(), goodJ[id].end());
		for(int j : goodJ[id]){
			if(j != last) add(j, 1);
			last = j;
		}
		for(auto [a, b, ind] : v){
			if(qry(a, b) != b-a+1) valid[ind] = false;
		}
		last = -1;
		for(int j : goodJ[id]){
			if(j != last) add(j, -1);
			last = j;
		}
	}
	for(const auto& [id, v] : byJ){
		int last = -1;
		for(int i : goodI[id]){
			if(i != last) add(i, 1);
			last = i;
		}
		for(auto [a, b, ind] : v){
			if(qry(a, b) != b-a+1) valid[ind] = false;
		}
		last = -1;
		for(int i : goodI[id]){
			if(i != last) add(i, -1);
			last = i;
		}
	}
	int ans = 0;
	for(bool b : valid) ans += b;
	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