Island count recursive January 14, 2018 - need to check compile error

islandCount_recursive_Jan14_2018.cs

using System;

class Solution
{
    static int getNumberOfIslands(int[,] binaryMatrix) { // 
    if(binaryMatrix == null || binaryMatrix.GetLength(0) == 0 || binaryMatrix.GetLength (1) == 0) // false 
    {
      return 0; 
    }
    
    int rows = binaryMatrix.GetLength(0) ; // 5
    int cols = binaryMatrix.GetLength(1); // 5
    
    int islandFound = 0; 
    
    for(int row = 0; row < rows; row++)
    {
      for(int col = 0; col < cols; col++)
      {
        var current = binaryMatrix[row, col]; // 0 , -1
        if(current != 1)
        {
          continue; 
        }
        
        visitIsland(binaryMatrix, row, col); 
        islandFound++; 
      }
    }
  }
  
  private void visitIsland(int[,] binaryMatrix, int startRow, int startCol) // 0, 1
  {
    int rows = binaryMatrix.GetLength(0) ; // 5
    int cols = binaryMatrix.GetLength(1); // 5
    
    
    if(binaryMatrix[startRow, startCol] != 1)
    {
      return; 
    }
    
    // mark visit 
    binaryMatrix[startRow, startCol] = -1; // -1
    
    // clockwise 4 neigbhors
    var leftCol = startCol - 1; 
    if(leftCol >= 0) // false
    {
      visitIsland(binaryMatrix, startRow, leftCol); 
    }
    
    // right
    var rightCol = startCol + 1; 
    
    if(startCol < (cols - 1)) // false 
    {
      visitIsland(binaryMatrix, startRow, rightCol); 
    }
    
    // top
    var topRow = startRow - 1;
    if(startRow > 0 ) // false 
    {
      visitIsland(binaryMatrix, topRow, startCol); 
    }
    
    // down 
    var downRow = startRow + 1;
    if(startRow < rows - 1)//false 
    {
      visitIsland(binaryMatrix, downRow, startCol); 
    }
  }

  public static void main(String[] args) {

  }
}