General implementation cleanup (#849)

* Monte Carlo [cpp]: Hardcode sample count

This removes the need for user input

* Verlet Integration [java]: Move VerletValue class into Verlet class

* Tree Traversal [java]: Move main method into Tree class

* Huffman Encoding [java]: Move Huffman class to the top of the file

Executing a single java file without compilation (in java >= 11) only works if the first
class it finds contains the main method.

Author: stormofice

contents/huffman_encoding/code/java/huffman.java

@@ -1,5 +1,15 @@
 import java.util.*;
 
+class Huffman {
+    public static void main(String[] args) {
+        HuffmanTree huffmanTree = new HuffmanTree("bibbity_bobbity");
+        huffmanTree.createTree();
+        String encoded = huffmanTree.encode();
+        System.out.println("Encoded String: " + encoded);
+        System.out.println("Decoded String: " + huffmanTree.decode(encoded));
+    }
+}
+
 class TreeNode {
     String letter = "";
     int frequency = 0;
@@ -101,13 +111,3 @@ public String decode(String encoded) {
         return decoded.toString();
     }
 }
-
-class Huffman {
-    public static void main(String[] args) {
-        HuffmanTree huffmanTree = new HuffmanTree("bibbity_bobbity");
-        huffmanTree.createTree();
-        String encoded = huffmanTree.encode();
-        System.out.println("Encoded String: " + encoded);
-        System.out.println("Decoded String: " + huffmanTree.decode(encoded));
-    }
-}

contents/monte_carlo_integration/code/c++/monte_carlo.cpp

@@ -39,10 +39,7 @@ double monte_carlo_pi(unsigned samples) {
 int main() {
     unsigned samples;
 
-    std::cout << "Enter samples to use: ";
-    std::cin >> samples;
-
-    double pi_estimate = monte_carlo_pi(samples);
+    double pi_estimate = monte_carlo_pi(10000000);
     std::cout << "Pi = " << pi_estimate << '\n';
     std::cout << "Percent error is: " << 100 * std::abs(pi_estimate - PI) / PI << " %\n";
 }

contents/tree_traversal/code/java/MainClass.java

@@ -124,4 +124,34 @@ public int compareTo(Node other) {
             return Integer.compare(this.id, other.id);
         }
     }
+    
+    public static void main(String[] args) {
+        System.out.println("Creating Tree");
+        Tree tree = new Tree(3, 3);
+
+        System.out.println("Using recursive DFS :");
+        tree.dfsRecursive();
+
+        System.out.println("Using stack-based DFS :");
+        tree.dfsStack();
+
+        System.out.println("Using queue-based BFS :");
+        tree.bfsQueue();
+
+        System.out.println("Using post-order recursive DFS :");
+        tree.dfsRecursivePostOrder();
+
+
+        // Uncommenting the following 2 lines will result in an exception thrown because at least one Node of the Tree has more than 2 children and therefor a DFSRecursiveInorderBinary doesn't work.
+        System.out.println("Using in-order binary recursive DFS : (fail)");
+        tree.dfsRecursiveInOrderBinary();
+
+        tree = new Tree(3, 2);
+        System.out.println("Using in-order binary recursive DFS : (succeed)");
+        tree.dfsRecursiveInOrderBinary();
+
+
+        System.out.println("");
+    }
+    
 }

contents/tree_traversal/code/java/Tree.java

@@ -330,8 +330,6 @@ Here is a video describing tree traversal:
 {% sample lang="java" %}
 ##### Tree.java
 [import, lang:"java"](code/java/Tree.java)
-##### MainClass.java
-[import, lang:"java"](code/java/MainClass.java)
 {% sample lang="js" %}
 [import, lang:"javascript"](code/javascript/tree.js)
 {% sample lang="py" %}

contents/tree_traversal/tree_traversal.md

@@ -1,4 +1,16 @@
 public class Verlet {
+    
+    private static class VerletValues {
+        public double time;
+        public double vel;
+    
+        public VerletValues(double time, double vel) {
+            this.time = time;
+            this.vel = vel;
+        }
+    }
+    
+
     static double verlet(double pos, double acc, double dt) {
 
       // Note that we are using a temp variable for the previous position

contents/verlet_integration/code/java/Verlet.java

@@ -37,7 +37,7 @@ Here is what it looks like in code:
 {% sample lang="c" %}
 [import:3-14, lang:"c"](code/c/verlet.c)
 {% sample lang="java" %}
-[import:2-17, lang:"java"](code/java/Verlet.java)
+[import:14-29, lang:"java"](code/java/Verlet.java)
 {% sample lang="py" %}
 [import:1-10, lang:"python"](code/python/verlet.py)
 {% sample lang="hs" %}
@@ -95,7 +95,7 @@ However, the error for this is $$\mathcal{O}(\Delta t)$$, which is quite poor, b
 {% sample lang="c" %}
 [import:16-31, lang:"c"](code/c/verlet.c)
 {% sample lang="java" %}
-[import:19-37, lang:"java"](code/java/Verlet.java)
+[import:31-49, lang:"java"](code/java/Verlet.java)
 {% sample lang="py" %}
 [import:12-23, lang:"python"](code/python/verlet.py)
 {% sample lang="hs" %}
@@ -167,7 +167,7 @@ Here is the velocity Verlet method in code:
 {% sample lang="c" %}
 [import:33-43, lang:"c"](code/c/verlet.c)
 {% sample lang="java" %}
-[import:39-51, lang:"java"](code/java/Verlet.java)
+[import:51-63, lang:"java"](code/java/Verlet.java)
 {% sample lang="py" %}
 [import:25-34, lang:"python"](code/python/verlet.py)
 {% sample lang="hs" %}
@@ -225,7 +225,6 @@ Both of these methods work simply by iterating timestep-by-timestep and can be w
 {% sample lang="c" %}
 [import, lang:"c"](code/c/verlet.c)
 {% sample lang="java" %}
-[import, lang:"java"](code/java/VerletValues.java)
 [import, lang:"java"](code/java/Verlet.java)
 {% sample lang="py" %}
 [import, lang:"python"](code/python/verlet.py)