private static int GetMinminutes(int[][] grid)
{
int rows = grid.Length;
if (rows == 0)
{
return(0);
}
List <int[]> dirs = new List <int[]>()
{
new[] { 0, 1 }, new[] { 1, 0 }, new[] { 0, -1 }, new[] { -1, 0 }
};
int minutes = 0, cols = grid[0].Length, freshOrange = 0;
Queue <Cordinate> rottenQueue = new Queue <Cordinate>();
for (int i = 0; i < grid.Length; i++)
{
for (int j = 0; j < grid[0].Length; j++)
{
if (grid[i][j] == 2)
{
rottenQueue.Enqueue(new Cordinate(i, j));
}
if (grid[i][j] == 1)
{
freshOrange++;
}
}
}
Console.WriteLine("Total rottenQueue :{0}, and freshOrange :{1}", rottenQueue.Count, freshOrange);
while (rottenQueue.Count > 0 && freshOrange > 0)
{
minutes++;
int qSize = rottenQueue.Count;
for (int i = 0; i < qSize; i++)
{
Cordinate cor = rottenQueue.Dequeue();
int x = cor.x;
int y = cor.y;
PrintMatrix(grid);
foreach (var dir in dirs)
{
int xNew = x + dir[0];
int yNew = y + dir[1];
if (IsValidOrage(grid, xNew, yNew, rows, cols))
{
grid[xNew][yNew] = 2;
rottenQueue.Enqueue(new Cordinate(xNew, yNew));
freshOrange--;
}
}
}
}
return(freshOrange == 0 ? minutes : -1);
}
private static int TreasureIslandIIDemo(char[][] grid)
{
int rows = grid.Length;
if (rows == 0)
{
return(0);
}
int cols = grid[0].Length, steps = 0;
bool[,] visited = new bool[rows, cols];
int[][] dirs = new[] { new[] { 1, 0 }, new[] { 0, 1 }, new[] { -1, 0 }, new[] { 0, -1 } };
Queue <Cordinate> queue = new Queue <Cordinate>();
for (int i = 0; i < rows; i++)
{
for (int j = 0; j < cols; j++)
{
if (grid[i][j] == 'S')
{
queue.Enqueue(new Cordinate(i, j));
visited[i, j] = true;
}
}
}
// No loop from all the starting points.
while (queue.Count > 0)
{
steps++;
int qSize = queue.Count;
for (int i = 0; i < qSize; i++)
{
Cordinate cor = queue.Dequeue();
int x = cor.x;
int y = cor.y;
PrintMatrix(visited);
foreach (var dir in dirs)
{
int xNew = x + dir[0];
int yNew = y + dir[1];
if (isSafe(grid, visited, xNew, yNew, rows, cols))
{
if (grid[xNew][yNew] == 'X')
{
return(steps);
}
visited[xNew, yNew] = true;
queue.Enqueue(new Cordinate(xNew, yNew));
}
}
}
}
return(-1);
}
private static int TreasureIslandBFS(char[][] grid)
{
int rows = grid.Length, steps = 0;
if (rows == 0)
{
return(steps);
}
int cols = grid[0].Length;
Queue <Cordinate> queue = new Queue <Cordinate>();
queue.Enqueue(new Cordinate(0, 0));
bool[,] visited = new bool[rows, cols];
visited[0, 0] = true;
int[][] directions = new[] { new[] { 1, 0 }, new[] { 0, 1 }, new[] { -1, 0 }, new[] { 0, -1 } };
//Start BFS
while (queue.Count > 0)
{
int levelSize = queue.Count;
for (int i = 0; i < levelSize; i++)
{
Cordinate cor = queue.Dequeue();
int x = cor.x;
int y = cor.y;
PrintMatrix(visited);
foreach (var dir in directions)
{
int newX = x + dir[0];
int newY = y + dir[1];
if (isValid(grid, visited, newX, newY, rows, cols))
{
if (grid[newX][newY] == 'X')
{
return(steps);
}
visited[newX, newY] = true;
queue.Enqueue(new Cordinate(newX, newY));
}
}
}
steps++;
}
return(-1);
}
private static int FindCutOff(IList <IList <int> > forest, int sr, int sc, int tx, int ty, int rows, int cols, int[][] dirs)
{
bool[,] seen = new bool[rows, cols];
Queue <Cordinate> treeQueue = new Queue <Cordinate>();
treeQueue.Enqueue(new Cordinate(sr, sc));
int step = 0;
while (treeQueue.Count > 0)
{
step++;
int qsize = treeQueue.Count;
for (int i = 0; i < qsize; i++)
{
Cordinate cor = treeQueue.Dequeue();
int x = cor.x;
int y = cor.y;
foreach (var dir in dirs)
{
int newX = x + dir[0];
int newY = y + dir[1];
if (x == newX && y == newY)
{
return(step);
}
if (newX >= 0 && newY >= 0 && newX < rows && newY < cols && forest[newX][newY] > 1 && seen[newX, newY] == false)
{
seen[newX, newY] = true;
treeQueue.Enqueue(new Cordinate(newX, newY));
}
}
}
}
return(-1);
}
private static int GetMinHours(int[][] grid)
{
int rows = grid.Length;
if (rows == 0)
{
return(0);
}
int cols = grid[0].Length;
int hours = 0;
List <int[]> dirs = new List <int[]> {
new int[] { 0, 1 }, new int[] { 1, 0 }, new int[] { 0, -1 }, new int[] { -1, 0 }
};
Queue <Cordinate> zomQueue = new Queue <Cordinate>();
int humCount = 0;
for (int i = 0; i < rows; i++)
{
for (int j = 0; j < cols; j++)
{
if (grid[i][j] == 1)
{
zomQueue.Enqueue(new Cordinate(i, j));
}
else
{
humCount++;
}
}
}
Console.WriteLine("Total zombie :{0}, and human :{1}", zomQueue.Count, humCount);
while (zomQueue.Count > 0 && humCount > 0)
{
hours++;
int qSize = zomQueue.Count;
for (int i = 0; i < qSize; i++)
{
Cordinate cor = zomQueue.Dequeue();
int x = cor.x;
int y = cor.y;
PrintMatrix(grid);
foreach (var dir in dirs)
{
int xNew = x + dir[0];
int yNew = y + dir[1];
if (IsValidHuman(grid, xNew, yNew, rows, cols))
{
grid[xNew][yNew] = 1;
zomQueue.Enqueue(new Cordinate(xNew, yNew));
humCount--;
}
}
}
}
return(humCount == 0 ? hours : -1);
}