1091-ShortestPathInBinaryMatrix.java

//Question Link - https://leetcode.com/problems/shortest-path-in-binary-matrix/

class Solution {
    public int shortestPathBinaryMatrix(int[][] g) {
        //base case
        if(g[0][0] == 1){
            return -1;
        }
        
        //using bfs
        int m = g.length, n = g[0].length, c = 0;
        Queue<int[]> nm = new LinkedList<>();
        
        nm.offer(new int[] {0, 0, 1});
        
        int d[][] = {{1,1},{-1,-1},{1,0},{-1,0},{0,1},{0,-1},{1,-1},{-1,1}};
        
        while(!(nm.isEmpty())){
            int l = nm.size();
            while(l --> 0){
                int f[] = nm.poll();
                
                if(f[0] == m-1 && f[1] == n-1){
                    return f[2];
                }
                
                for(int k[]: d){
                    int i = f[0] + k[0];
                    int j = f[1] + k[1];
                    if(i>=0 && j>=0 && i<m && j<n && g[i][j] == 0){
                        nm.offer(new int[] {i, j, f[2]+1});
                        g[i][j] = 1;
                    }
                }
            }
        }
        
        return -1;
    }
}