Submission #1153150

#	Time	Username	Problem	Language	Result	Execution time	Memory
1153150		mertbbm	Maze (JOI23_ho_t3)	C++20	100 / 100	732 ms	570012 KiB

Main

#include <bits/stdc++.h>
using namespace std;
 
#define int long long 
#define ld long double
#define show(x,y) cout << y << " " << #x << endl;
#define show2(x,y,i,j) cout << y << " " << #x << "  " << j << " " << #i << endl;
#define show3(x,y,i,j,p,q) cout << y << " " << #x << "  " << j << " " << #i << "  " << q << " " << #p << endl;
#define show4(x,y) for(auto it:y) cout << it << " "; cout << #x << endl;
typedef pair<int,int>pii;
typedef pair<pii,int>pi2;
mt19937_64 rng(chrono::system_clock::now().time_since_epoch().count());

void solve(){
	int n,m,k;
	cin >> n >> m >> k;
	
	pii st;
	pii ed;
	cin >> st.first >> st.second >> ed.first >> ed.second;
	
	st.first--;
	st.second--;
	ed.first--;
	ed.second--;
	
	string arr[n];
	for(int x=0;x<n;x++){
		cin >> arr[x];
	}

	pii dir[8]={
		{1,0},
		{-1,0},
		{0,1},
		{0,-1},
		{1,1},
		{-1,-1},
		{1,-1},
		{-1,1},
	};
	
	int dist[n+5][m+5];
	int ans[n+5][m+5];
	memset(dist,-1,sizeof(dist));
	memset(ans,-1,sizeof(ans));
	vector<pii>black;
	vector<pii>white;
	white.push_back(st);

	for(int x=0;x<n+m+2;x++){
		//bfs out
		if(x>0){
			queue<pii>q;
			for(auto it:black){
				if(ans[it.first][it.second]!=-1) continue;
				q.push(it);
				dist[it.first][it.second]=0;
			}
			
			black.clear();
			
			while(!q.empty()){
				pii cur=q.front();
				q.pop();
				if(ans[cur.first][cur.second]!=-1) continue;
				ans[cur.first][cur.second]=x;
				for(auto it:dir){
					int nx=cur.first+it.first;
					int ny=cur.second+it.second;
					int nd=dist[cur.first][cur.second]+1;
					if(nx<0||ny<0||nx>=n||ny>=m) continue;
					if(dist[nx][ny]!=-1&&dist[nx][ny]<=nd) continue;
					if(ans[nx][ny]!=-1) continue;
					if(nd>=k){
						if(abs(it.first)+abs(it.second)==1){
							if(arr[nx][ny]=='.') white.push_back({nx,ny});
							else black.push_back({nx,ny});
						}
						continue;
					}
					dist[nx][ny]=nd;
					q.push({nx,ny});
				}
			}
		}
		//white
		{
			queue<pii>q;
			for(auto it:white){
				if(ans[it.first][it.second]!=-1) continue;
				q.push(it);
			}
			
			white.clear();
			while(!q.empty()){
				pii cur=q.front();
				q.pop();
				if(ans[cur.first][cur.second]!=-1) continue;
				ans[cur.first][cur.second]=x;
				for(auto it:dir){
					if(abs(it.first)+abs(it.second)!=1) continue;
					int nx=cur.first+it.first;
					int ny=cur.second+it.second;
					if(nx<0||ny<0||nx>=n||ny>=m) continue;
					if(ans[nx][ny]!=-1) continue;
					if(arr[nx][ny]=='.'){
						q.push({nx,ny});
					}
					else{
						black.push_back({nx,ny});
					}
				}
			}
		}
	}
	
	cout << ans[ed.first][ed.second] << "\n";
}

int32_t main(){
	ios::sync_with_stdio(0);
	cin.tie(0);
	//freopen("in.txt","r",stdin);
	//freopen("in.txt","w",stdout);
	int t=1;	        
	//cin >> t;	
	while(t--){
		solve(); 
	}
}

• Subtask 1: 8 / 8
• Subtask 2: 19 / 19
• Subtask 3: 16 / 16
• Subtask 4: 19 / 19
• Subtask 5: 5 / 5
• Subtask 6: 19 / 19
• Subtask 7: 8 / 8
• Subtask 8: 6 / 6