Submission #391162

#	Time	Username	Problem	Language	Result	Execution time	Memory
391162		keta_tsimakuridze	Furniture (JOI20_furniture)	C++14	100 / 100	2301 ms	36732 KiB

furniture

#include<bits/stdc++.h>
#define f first
#define int long long
#define s second
using namespace std;
const int N=1005,mod=1e9+7;
int t,d2[N][N],d1[N][N],p[N][N],n,m,cnt[2*N];
queue<pair<int,int> > q;
char c[N][N];
bool ok(int x,int y){
	if(min(x,y)<1 || x>n || y>m) return 0;
	return 1;
}
void dfs1(int x,int y){
	if(d1[x][y] || c[x][y]=='1') return;
	d1[x][y]=1;
	if(ok(x+1,y)) dfs1(x+1,y);
	if(ok(x,y+1)) dfs1(x,y+1);
}
void dfs2(int x,int y){
	if(d2[x][y] || c[x][y]=='1') return;
	d2[x][y]=1; 
	if(ok(x-1,y)) dfs2(x-1,y);
	if(ok(x,y-1)) dfs2(x,y-1);
}
void update1(int x,int y){
	if(ok(x+1,y) && p[x+1][y] && !p[x+1][y-1]) q.push({x+1,y});	
	if(ok(x,y+1) && p[x][y+1] && !p[x-1][y+1]) q.push({x,y+1});	
	while(q.size()){
		x=q.front().f;
		y=q.front().s;
		q.pop();
		if(p[x][y-1] || p[x-1][y]) continue;
		p[x][y]=0; cnt[x+y]--;
		if(ok(x+1,y) && p[x+1][y] && !p[x+1][y-1]) q.push({x+1,y});	
		if(ok(x,y+1) && p[x][y+1] && !p[x-1][y+1]) q.push({x,y+1});	
	}
}
void update2(int x,int y){
	if(ok(x-1,y) && p[x-1][y] && !p[x-1][y+1]) q.push({x-1,y});	
	if(ok(x,y-1) && p[x][y-1] && !p[x+1][y-1]) q.push({x,y-1});	
	while(q.size()){
		x=q.front().f;
		y=q.front().s;
		q.pop(); 
		if(p[x][y+1] || p[x+1][y]) continue;
		p[x][y]=0; cnt[x+y]--;
		if(ok(x-1,y) && p[x-1][y] && !p[x-1][y+1]) q.push({x-1,y});	
		if(ok(x,y-1) && p[x][y-1] && !p[x+1][y-1]) q.push({x,y-1});	
	}
}
 main(){
	// t=1;
	cin>>n>>m;
	for(int i=1;i<=n;i++){
		for(int j=1;j<=m;j++){
			cin>>c[i][j];
		}
	}
	dfs1(1,1);
	dfs2(n,m); d1[1][1]=d2[n][m]=1;
	for(int i=1;i<=n;i++){
		for(int j=1;j<=m;j++){
			if(d1[i][j] && d2[i][j]) p[i][j]=1,cnt[i+j]++;
		
		}
	}
	int q;
	cin>>q;
	while(q--){
		int a,b;
		cin>>a>>b;
		if(!p[a][b] ) {
			cout<<1<<endl;
		}
		else {
			if(cnt[a+b]-1){ 
				p[a][b]=0; 
				cnt[a+b]--;
				update1(a,b);
				update2(a,b);
				cout<<1<<endl;
			}
			else cout<<0<<endl;
		}
	}
	
}

Compilation message (stderr)

furniture.cpp:52:7: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
   52 |  main(){
      |       ^

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