Start to work on Huffman encoding exercise

src/huffman.rs

@@ -0,0 +1,5 @@
+
+pub struct HuffmanAlphabet {
+	pub length: u32,
+	pub frequencies: Vec<u32>,
+}

src/main.rs

@@ -129,6 +129,6 @@ fn main() {
     // c2a3();
     // c2a4();
     // c3a1();
-    c3a2();
+    // c3a2();
     c3a3();
 }