Bootcamp Challenges

image_blur.rb

class Image

  def initialize(image)
      @image = image
  end

  def displayImage
    @image.each{|row| puts row.join}
  end

  def blur(dist = 1)
    coords = []
    @image.each_with_index do |row_data, row|
      row_data.each_with_index do |col_data, col|
        coords << [row, col] if col_data == 1
      end
    end

    coords.each do |coord|
      row,col = coord
      1.upto(dist) do |d|
        0.upto(dist-d) do |i|
          # top-left quadrant
          @image[row - i][col - d] = 1 unless row - i < 0 || col + d >= @image.length
          # top-right quadrant
          @image[row - d][col + i] = 1 unless row - d < 0 || col + i >= @image.length
          # bottom-right quadrant
          @image[row + i][col + d] = 1 unless row + i >= @image.length || col + d >= @image.length
          # bottom-left quadrant
          @image[row + d][col - i] = 1 unless row + d >= @image.length || col - i < 0
        end
      end
    end

    self.displayImage
  end

end

image = Image.new([
  [0,0,0,0,0,0,0,0,0],
  [0,0,0,0,0,0,0,0,0],
  [0,0,0,0,0,0,0,0,0],
  [0,0,0,0,0,0,0,0,0],
  [0,0,0,0,1,0,0,0,0],
  [0,0,0,0,0,0,0,0,0],
  [0,0,0,0,0,0,0,0,0],
  [0,0,0,0,0,0,0,0,0],
  [0,0,0,0,0,0,0,0,0]
])

image.blur(2)

image_blur_v2.rb

class Image

  def initialize(image)
      @image = image
  end

  def displayImage
    @image.each{|row| puts row.join}
  end

  def blur(dist = 1)
    coords = []
    @image.each_with_index do |row_data, row|
      row_data.each_with_index do |col_data, col|
        coords << [row, col] if col_data == 1
      end
    end

    coords.each do |coord|
      row,col = coord
      dist.downto(-dist) do |d|
        # center column
        unless row - d < 0 || row + d >= @image.length
          @image[row - d][col] = 1
          1.upto(dist-d.abs) do |i|
            #right side
            @image[row - d][col + i] = 1 unless col + i >= @image.length
            #left side
            @image[row - d][col - i] = 1 unless col - i < 0
          end
        end
      end
    end
    self.displayImage
  end

end

image = Image.new([
  [1,0,0,0,0,0,0,0,0],
  [0,0,0,0,0,0,0,0,0],
  [0,0,0,0,0,0,0,0,0],
  [0,0,0,0,0,0,0,0,0],
  [0,0,0,0,1,0,0,0,0],
  [0,0,0,0,0,0,0,0,0],
  [0,0,0,0,0,0,0,0,0],
  [0,0,0,0,0,0,0,0,0],
  [0,0,0,0,0,0,0,0,0]
])

image.blur(3)

linked_list1.rb

class LinkedListNode
  attr_accessor :value, :next_node

  def initialize(value, next_node=nil)
    @value = value
    @next_node = next_node
  end
end

class Stack
    attr_reader :data

    def initialize
        @data = nil
    end

    def push(value)
      @data = LinkedListNode.new(value, @data)
    end

    def pop
      if @data then
        r = @data.value;
        @data = @data.next_node
      else
        r = nil
      end
      return r
    end

end


def print_list(stack)
  data = stack.data

  begin
    print "#{data.value} --> "
    data = data.next_node
  end while data
  print "nil\n"
  return
end

def reverse_list(stack)
    reverse_stack = Stack.new
    while stack.data
      reverse_stack.push(stack.pop);
    end

    return print_list(reverse_stack)
end

myStack = Stack.new
myStack.push(37)
myStack.push(99)
myStack.push(12)
myStack.push(544)
myStack.push(34)
myStack.push(87)
myStack.push(2)
print_list(myStack)
puts "-------"
reverse_list(myStack)