updating DIRECTORY.md

Author: pre-commit-ci[bot]

DIRECTORY.md

@@ -522,6 +522,7 @@
 
 ## [Fractals](fractals)
   * [Barnsley Fern](fractals/barnsley_fern.py)
+  * [Hilbert Curve](fractals/hilbert_curve.py)
   * [Julia Sets](fractals/julia_sets.py)
   * [Koch Snowflake](fractals/koch_snowflake.py)
   * [Mandelbrot](fractals/mandelbrot.py)
@@ -699,7 +700,7 @@
   * [Gradient Descent](machine_learning/gradient_descent.py)
   * [K Means Clust](machine_learning/k_means_clust.py)
   * [K Medoids](machine_learning/k_medoids.py)
-  * [K Nearest Neighbours](machine_learning/k_nearest_neighbours.py)
+  * [K Nearest Neighbors](machine_learning/k_nearest_neighbors.py)
   * [Linear Discriminant Analysis](machine_learning/linear_discriminant_analysis.py)
   * [Linear Regression](machine_learning/linear_regression.py)
   * [Linear Regression Vectorized](machine_learning/linear_regression_vectorized.py)
@@ -742,6 +743,7 @@
   * [Binary Multiplication](maths/binary_multiplication.py)
   * [Binomial Coefficient](maths/binomial_coefficient.py)
   * [Binomial Distribution](maths/binomial_distribution.py)
+  * [Binomial Expansion](maths/binomial_expansion.py)
   * [Ceil](maths/ceil.py)
   * [Chebyshev Distance](maths/chebyshev_distance.py)
   * [Check Polygon](maths/check_polygon.py)
@@ -785,6 +787,7 @@
   * [Interquartile Range](maths/interquartile_range.py)
   * [Is Int Palindrome](maths/is_int_palindrome.py)
   * [Is Ip V4 Address Valid](maths/is_ip_v4_address_valid.py)
+  * [Is Ipv6 Address Valid](maths/is_ipv6_address_valid.py)
   * [Is Square Free](maths/is_square_free.py)
   * [Jaccard Similarity](maths/jaccard_similarity.py)
   * [Joint Probability Distribution](maths/joint_probability_distribution.py)