public IList<Node> getListOfBuilding(int[][] grid)
{
IList<Node> list = new List<Node>();
if (grid == null || grid.Length == 0)
return list;
int m = grid.Length;
int n = grid[0].Length;
for (int i = 0; i < m; i++)
for (int j = 0; j < n; j++)
{
if (grid[i][j] == BUILDING)
{
Node node = new Node(i, j);
list.Add(node);
}
}
return list;
}
/*
* Design a BFS function - most challenge one
* 1. in the range of matrix
2. is not the building node - original starter
3. is land node
*
* bug 001 - do not allow
* declare statement:
* int x = originalNode.x
* x scope is bigger than necessary, in while loop area - causing bug
*
*/
public void BFS(Node origNode,
int currDistance,
ref int[][] dist,
ref int[][] reach,
int[][] grid,
ref bool[][] visited,
ref Queue<Node> queue
)
{
// add first node into the queue
fill(origNode.x, origNode.y, origNode.x, origNode.y, currDistance,
ref dist, ref reach, grid, ref visited, ref queue);
while (queue.Count > 0)
{
Node node = queue.Dequeue();
int x = node.x; // bug 001
int y = node.y;
currDistance++; // BUG-B-02 CANNOT USE ONE VARIABLE FOR DISTANCE - NEED TO SAVE IN THE QUEUE, RETRIEVE FROM QUEUE
// four directions - call fill function
fill(x, y, x - 1, y, currDistance, ref dist, ref reach, grid, ref visited, ref queue);
fill(x, y, x + 1, y, currDistance, ref dist, ref reach, grid, ref visited, ref queue);
fill(x, y, x, y - 1, currDistance, ref dist, ref reach, grid, ref visited, ref queue);
fill(x, y, x, y + 1, currDistance, ref dist, ref reach, grid, ref visited, ref queue);
}
}
