Submission #827784

#	Time	Username	Problem	Language	Result	Execution time	Memory
827784		Baytoro	Rectangles (IOI19_rect)	C++17	50 / 100	5064 ms	548028 KiB

rect

#include "rect.h"
//#include "grader.cpp"
#include <bits/stdc++.h>
using namespace std;
#define pb push_back
#define fr first
#define sc second
const int N=2505;
int a[N][N],b[N],c[N],used[N][N];
int l,r,lx,rx,cnt,n,m;
void dfs(int x, int y){
	if(x==0 || y==0) return;
	if(x>n || y>m) return;
	if(a[x][y] || used[x][y]) return;
	used[x][y]=1;
	cnt++;
	l=min(l,x);
	r=max(r,x);
	lx=min(lx,y);
	rx=max(rx,y);
	if(!used[x+1][y]) dfs(x+1,y);
	if(!used[x-1][y]) dfs(x-1,y);
	if(!used[x][y+1]) dfs(x,y+1);
	if(!used[x][y-1]) dfs(x,y-1);
}
long long count_rectangles(vector<vector<int>> A) {
	n=A.size();
	m=A[0].size();
	if(min(n,m)<3) return 0;
	int mx=0;
	for(int i=0;i<n;i++){
		for(int j=0;j<m;j++)
			a[i+1][j+1]=A[i][j],mx=max(mx,A[i][j]);
	}
	int ans=0;
	if(mx<=1){
		for(int i=2;i<n;i++){
			for(int j=2;j<m;j++){
				if(used[i][j]) continue;
				l=1e9;
				r=0;
				lx=1e9;
				rx=0;
				cnt=0;
				dfs(i,j);
				if(l==1 || r==n) continue;
				if(lx==1 || rx==m) continue;
				if(cnt==(r-l+1)*(rx-lx+1))
					ans++;
			}
		}
	}
	else if(n<=3 || (n<=2500 && m<=2500)){
		for(int l=2;l<n;l++){
			for(int r=l;r<n;r++){
				for(int i=1;i<=m;i++){
					if(l==r) b[i]=a[l][i];
					else b[i]=max(b[i],a[r][i]);
				}
				for(int i=2;i<m;i++){
					for(int j=i;j<m;j++){
						if(b[j]>=min(a[l-1][j],a[r+1][j])) break;
						bool cnt=1;
						for(int k=l;k<=r;k++){
							if(i==j) c[k]=a[k][j];
							else c[k]=max(c[k],a[k][j]);
							if(c[k]>=min(a[k][i-1],a[k][j+1])){
								cnt=0;
							}
						}
						ans+=cnt;
					}
				}
			}
		}
	}
	return ans;
}

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