minor fix

src/mlpack/methods/decision_tree/fitness_functions/gini_gain.hpp

@@ -1,5 +1,5 @@
 /**
- * @file methods/decision_tree/gain_functions/gini_gain.hpp
+ * @file methods/decision_tree/fitness_functions/gini_gain.hpp
  * @author Ryan Curtin
  *
  * The GiniGain class, which is a fitness function (FitnessFunction) for

src/mlpack/methods/decision_tree/fitness_functions/information_gain.hpp

@@ -1,5 +1,5 @@
 /**
- * @file methods/decision_tree/gain_functions/information_gain.hpp
+ * @file methods/decision_tree/fitness_functions/information_gain.hpp
  * @author Ryan Curtin
  *
  * An implementation of information gain, which can be used in place of Gini

src/mlpack/methods/decision_tree/fitness_functions/mad_gain.hpp

@@ -1,5 +1,5 @@
 /**
- * @file methods/decision_tree/gain_functions/mad_gain.hpp
+ * @file methods/decision_tree/fitness_functions/mad_gain.hpp
  * @author Rishabh Garg
  *
  * The mean absolute deviation gain class, a fitness function for regression

src/mlpack/methods/decision_tree/fitness_functions/mse_gain.hpp

@@ -1,5 +1,5 @@
 /**
- * @file methods/decision_tree/gain_functions/mse_gain.hpp
+ * @file methods/decision_tree/fitness_functions/mse_gain.hpp
  * @author Rishabh Garg
  *
  * The mean squared error gain class, which is a fitness funtion for