public int orangesRotting(int[][] grid) {

if(grid.length==0) return -1;

int rows= grid.length;

int cols = grid[0].length;

int result =0;

int freshOranges =0;

Deque<int[]> queue = new ArrayDeque<>();

for(int i=0;i< grid.length;i++){

for(int j=0;j<grid[0].length;j++){

if(grid[i][j]==1){

freshOranges++;

}

else if(grid[i][j]==2){

queue.add(new int[]{i, j});

}

}

}

while(!queue.isEmpty() && freshOranges!=0){

int queueLength = queue.size();

result++;

for (int i = 0; i < queueLength; i++) {

int[] rotten = queue.poll();

int r = rotten[0], c = rotten[1];

int[][] neighbors = {{r, c + 1}, {r, c - 1}, {r + 1, c}, {r - 1, c}};

for (int j = 0; j < 4; j++) {

int newR = neighbors[j][0], newC = neighbors[j][1];

if (Math.min(newR, newC) < 0 || newR == rows || newC == cols

|| grid[newR][newC] != 1) {

continue;

}

freshOranges--;

queue.add(neighbors[j]);

grid[newR][newC] = 2;

}

}

}

if(freshOranges>0){

return -1;

}

return result;

}