Submission #292585

#	Time	Username	Problem	Language	Result	Execution time	Memory
292585		kshitij_sodani	Furniture (JOI20_furniture)	C++14	100 / 100	397 ms	18168 KiB

furniture

#include <bits/stdc++.h>
using namespace std;
typedef long long llo;
#define mp make_pair
#define pb push_back
#define a first 
#define b second
#define endl '\n' 

int n,m;
int it[1001][1001];
int vis[1001][1001];
int vis2[1001][1001];
int val[1001][1001];
int co[3001];

int cal(int i,int j){
	int co=0;
	if(i+1<n){
		co+=val[i+1][j];
	}
	if(j+1<m){
		co+=val[i][j+1];
	}
	return co;
}
int cal2(int i,int j){
	int co=0;
	if(i>0){
		co+=val[i-1][j];
	}
	if(j>0){
		co+=val[i][j-1];
	}
	return co;
}
void dfs(int aa,int bb){
	val[aa][bb]=0;
	co[aa+bb]-=1;
	if(aa>0){
		if(val[aa-1][bb]){
			if(cal(aa-1,bb)==0){
				dfs(aa-1,bb);
			}
		}
	}
	if(bb>0){
		if(val[aa][bb-1]){
			if(cal(aa,bb-1)==0){
				dfs(aa,bb-1);
			}
		}
	}
}
void dfs2(int aa,int bb){
	val[aa][bb]=0;
	co[aa+bb]-=1;
	if(aa<n-1){
		if(val[aa+1][bb]){
			if(cal2(aa+1,bb)==0){
				dfs2(aa+1,bb);
			}
		}
	}
	if(bb<m-1){
		if(val[aa][bb+1]){
			if(cal2(aa,bb+1)==0){
				dfs2(aa,bb+1);
			}
		}
	}
}
int main(){
	ios_base::sync_with_stdio(false);
	cin.tie(NULL);
	cin>>n>>m;
	for(int i=0;i<n;i++){
		for(int j=0;j<m;j++){
			cin>>it[i][j];
		}
	}
	vis[n-1][m-1]=1;
	for(int i=n-1;i>=0;i--){
		for(int j=m-1;j>=0;j--){
			if(i==n-1 and j==m-1){
				continue;
			}
			if(it[i][j]==0){
				if(i<n-1){
					vis[i][j]|=vis[i+1][j];
				}
				if(j<m-1){
					vis[i][j]|=vis[i][j+1];
				}
			}
		}
	}
	vis2[0][0]=1;
	for(int i=0;i<n;i++){
		for(int j=0;j<m;j++){
			if(it[i][j]==1){
				continue;
			}
			if(i==0 and j==0){
				continue;
			}
			if(i>0){
				vis2[i][j]|=vis2[i-1][j];
			}
			if(j>0){
				vis2[i][j]|=vis2[i][j-1];
			}
		}
	}
	for(int i=0;i<n;i++){
		for(int j=0;j<m;j++){
			if(vis2[i][j] and vis[i][j]){
				val[i][j]=1;
				co[i+j]+=1;
			}
		}
	}

	int q;
	cin>>q;
	while(q--){
		int aa,bb;
		cin>>aa>>bb;
		aa--;
		bb--;
		if(val[aa][bb]==0){
			cout<<1<<endl;
			continue;
		}
		if(co[aa+bb]==1){
			cout<<0<<endl;
			continue;
		}
		else{
			dfs(aa,bb);
			dfs2(aa,bb);
			co[aa+bb]+=1;
			cout<<1<<endl;
		}
	}















	return 0;
}

• Subtask 1: 5 / 5
• Subtask 2: 95 / 95