Formula based 2D Matrix
matrix = lambda { |x| lambda { |y| x*y**2 }}
p matrix[-3][-10] #=> -300
p matrix[0][0] #=> 0
p matrix[3][4] #=> 48
p matrix[10][20] #=> 4000
matrix = lambda { |x| lambda { |y| x*y**2 }}
p matrix[-3][-10] #=> -300
p matrix[0][0] #=> 0
p matrix[3][4] #=> 48
p matrix[10][20] #=> 4000
