updating DIRECTORY.md

Author: github-actions

DIRECTORY.md

@@ -13,7 +13,7 @@
   * [Bisection Method](https://github.com/TheAlgorithms/C-Plus-Plus/blob/master/computer_oriented_statistical_methods/Bisection_method.CPP)
   * [False-Position](https://github.com/TheAlgorithms/C-Plus-Plus/blob/master/computer_oriented_statistical_methods/false-position.cpp)
   * [Gaussian Elimination](https://github.com/TheAlgorithms/C-Plus-Plus/blob/master/computer_oriented_statistical_methods/Gaussian_elimination.cpp)
-  * [Newton Raphson](https://github.com/TheAlgorithms/C-Plus-Plus/blob/master/computer_oriented_statistical_methods/Newton_Raphson.CPP)
+  * [Newton Raphson Method](https://github.com/TheAlgorithms/C-Plus-Plus/blob/master/computer_oriented_statistical_methods/newton_raphson_method.cpp)
   * [Ordinary Least Squares Regressor](https://github.com/TheAlgorithms/C-Plus-Plus/blob/master/computer_oriented_statistical_methods/ordinary_least_squares_regressor.cpp)
   * [Secant Method](https://github.com/TheAlgorithms/C-Plus-Plus/blob/master/computer_oriented_statistical_methods/Secant_method.CPP)
   * [Successive Approximation](https://github.com/TheAlgorithms/C-Plus-Plus/blob/master/computer_oriented_statistical_methods/successive_approximation.CPP)
@@ -116,7 +116,7 @@
   * [Power For Huge Numbers](https://github.com/TheAlgorithms/C-Plus-Plus/blob/master/math/power_for_huge_numbers.cpp)
   * [Prime Factorization](https://github.com/TheAlgorithms/C-Plus-Plus/blob/master/math/prime_factorization.cpp)
   * [Prime Numbers](https://github.com/TheAlgorithms/C-Plus-Plus/blob/master/math/prime_numbers.cpp)
-  * [Primes Up To 10^8](https://github.com/TheAlgorithms/C-Plus-Plus/blob/master/math/primes_up_to_10^8.cpp)
+  * [Primes Up To Billion](https://github.com/TheAlgorithms/C-Plus-Plus/blob/master/math/primes_up_to_billion.cpp)
   * [Sieve Of Eratosthenes](https://github.com/TheAlgorithms/C-Plus-Plus/blob/master/math/sieve_of_eratosthenes.cpp)
   * [Sqrt Double](https://github.com/TheAlgorithms/C-Plus-Plus/blob/master/math/sqrt_double.cpp)