public static int Solve(string fileName, char shapeChar)
{
string[] lines = File.ReadAllLines(fileName);
var rows = int.Parse(lines[0]);
var cols = int.Parse(lines[1]);
lines = lines.Skip(2).ToArray();
UnionFindNode <char>[] nodes = new UnionFindNode <char> [rows * cols];
for (int r = 0; r < rows; r++)
{
string line = lines[r];
for (int c = 0; c < cols; c++)
{
UnionFindNode <char> current = new UnionFindNode <char>(line[c]);
nodes[c * rows + r] = current;
if (c > 0)
{
Combine(current, nodes[(c - 1) * rows + r], current.Value);
}
if (r > 0)
{
Combine(current, nodes[c * rows + r - 1], current.Value);
}
}
}
return(nodes.Where(x => x.Value == shapeChar).Select(x => x.Find()).Distinct().Count());
}