Submission #1070104

#	Time	Username	Problem	Language	Result	Execution time	Memory
1070104		PotatoTheWarriorFRTT	Rectangles (IOI19_rect)	C++14	10 / 100	444 ms	604 KiB

rect

#include "rect.h"
#include <bits/stdc++.h>
using namespace std;
 
typedef long long ll;

void build(int tree[], int a[], int v, int l, int r) {
	if(l == r) {
		tree[v] = a[l];
	}else{
		int m = (l+r)/2;
		build(tree, a, 2*v, l, m);
		build(tree, a, 2*v+1, m+1, r);
		tree[v] = max(tree[2*v], tree[2*v+1]);
	}
}
int query(int tree[], int a[], int tl, int tr, int v, int l, int r) {
	if(tr < tl || r < l) {
		return 0;
	}else if(tr == r && tl == l) {
		return tree[v];
	}else{
		int m = (l+r)/2;
		return max(
			query(tree, a, tl, min(tr, m), 2*v, l, m), query(tree, a, max(tl, m+1), tr, 2*v+1, m+1, r)
		);
	}
}

long long count_rectangles(vector<vector<int>> a) {
	int n = a.size();
	int m = a[0].size();
	if(n <=2 || m<=2) {
		return 0;
	}else if(n == 3) {
		int good[m+1];
		for(int i=1;i<=m-2;i++) {
			good[i] = (a[1][i] < a[0][i] && a[1][i] < a[2][i]);
		}
		vector<pair<int, int>> vec;
		int arr[m];
		int tree[4*m];
		for(int i=1;i<=m-2;i++) {
			arr[i-1] = a[1][i];
		}
		for(int i=1;i<=m-2;i++) {
			if(good[i]) {
				vec.push_back({i, i});
				i++;
				while(i<=m-2 && good[i]) {
					vec[vec.size()-1].second++;
					i++;
				}
				i--;
			}
		}
		build(tree, arr, 1, 0, m-3);
		int ans = 0;
		for(int k=0;k<vec.size();k++) {
			int s = vec[k].first;
			int e = vec[k].second;
			for(int i=s;i<=e;i++) {
				for(int j=i;j<=e;j++) {
					int ma = query(tree, arr, i-1, j-1, 1, 0, m-3);
					if(ma < a[1][i-1] && ma < a[1][j+1]) {
						ans++;
					}
				}
			}
		}
		return ans;
	}
	return 0;
}

Compilation message (stderr)

rect.cpp: In function 'long long int count_rectangles(std::vector<std::vector<int> >)':
rect.cpp:59:16: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   59 |   for(int k=0;k<vec.size();k++) {
      |               ~^~~~~~~~~~~

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