fork download
copy 
  1. import java.util.*;
  2. import java.lang.*;
  3. import java.io.*;
  4.  
  5. class Codechef {
  6.     public static int bfs(char[][] grid,int n,int m) {
  7.         if (grid[0][0]=='#'||grid[n-1][m-1]=='#')return -1;
  8.  
  9.         Queue<int[]>q=new LinkedList<>();
  10.         boolean[][]visited=new boolean[n][m];
  11.         q.add(new int[]{0,0,0});
  12.         visited[0][0]=true;
  13.         int[][]dirs={{1,0},{-1,0},{0,1},{0,-1}};
  14.  
  15.         while(!q.isEmpty()){
  16.             int[]cell=q.poll();
  17.             int r=cell[0], c=cell[1], dist=cell[2];
  18.             if (r==n-1 && c==m-1)return dist;
  19.             for (int[]d:dirs){
  20.                 int nr= r+d[0], nc=c+d[1];
  21.                 if (nr>=0 && nr<n && nc>=0 && nc<m && !visited[nr][nc] && grid[nr][nc]=='.'){
  22.                     visited[nr][nc]=true;
  23.                     q.add(new int[]{nr,nc,dist+1});
  24.                 }
  25.             }
  26.         }
  27.         return -1;
  28.     }
  29.  
  30.     public static void main (String[] args) throws java.lang.Exception
  31. 	{
  32. 		// your code goes here
  33.         Scanner sc=new Scanner(System.in);
  34.         int n=sc.nextInt();
  35.         int m=sc.nextInt();
  36.         sc.nextLine();
  37.         char[][]grid=new char[n][m];
  38.         for (int i=0;i<n;i++){
  39.             String val=sc.nextLine();
  40.             for (int j=0;j<m && j<val.length();j++){
  41.                 grid[i][j]=val.charAt(j);
  42.             }
  43.         }
  44.         int out=bfs(grid,n,m);
  45.         System.out.println(out);
  46.         sc.close();
  47.     }
  48. }
Success #stdin #stdout 0.15s 56568KB
comments (?)
stdin
copy 
2 4
...#
##..
stdout
copy 
4
https://ideone.com/EPSlAQ
language:
Java (HotSpot 12)
created:
3 days ago
visibility:
public

Share or Embed source code

Discover > Sphere Engine API

The brand new service which powers Ideone!

Discover > IDE Widget

Widget for compiling and running the source code in a web browser!