47. 1926. Nearest Exit from Entrance in Maze

class Solution {
    public int nearestExit(char[][] maze, int[] entrance) {
        int m = maze.length;
        int n = maze[0].length;
        int [][]directions = {{0,1},{0,-1},{1,0},{-1,0}};//right,left,down,up

        Queue<int[]> queue = new LinkedList<>();
        queue.offer(entrance);

        maze[entrance[0]][entrance[1]] ='+';
        int step=0;
        while(!queue.isEmpty()){
            int size = queue.size();

            for(int i=0;i<size;i++){
                int []curr=queue.poll();

                //check if current is exit point or not and also we check it is not an entrance point
                if((curr[0] != entrance[0] || curr[1] != entrance[1])&&(curr[0] ==0 || curr[0] ==m-1 || curr[1] ==0 || curr[1] == n-1 )){
                    return step++;
                }
                 //now we check neighbours 
                for(int [] dir: directions){
                    int newRow = curr[0] + dir[0];
                    int newCol = curr[1] + dir[1];
                    //if newRow and newCol is valid and not visit then we add this is our queue
                    if((newRow>=0 &&newRow<m &&newCol>=0&&newCol<n)&& maze[newRow][newCol]=='.'){
                        maze[newRow][newCol]='+';
                        queue.offer(new int[]{newRow,newCol});
                    }
                }

            }

           
            //increase step
            step++;
        }
        //if exit not found 
        return -1;
        
    }
}