ch08 revisions

ChrisMayfield · ChrisMayfield · commit 4ce61936e55c · 2020-06-17T15:09:19.000-04:00
diff --git a/ch08/CodingBat.java b/ch08/CodingBat.java
@@ -3,26 +3,35 @@
  */
 public class CodingBat {
 
-    public static String noX(String str) {
+    /**
+     * See https://codingbat.com/prob/p118230.
+     */
+    public String noX(String str) {
         if (str.length() == 0) {
             return "";
         }
-        char c = str.charAt(0);
-        if (c == 'x') {
-            return noX(str.substring(1));
+        char first = str.charAt(0);
+        String rest = str.substring(1);
+        String recurse = noX(rest);
+        if (first == 'x') {
+            return recurse;
         } else {
-            return c + noX(str.substring(1));
+            return first + recurse;
         }
     }
 
+    /**
+     * See https://codingbat.com/prob/p135988.
+     */
     public int array11(int[] nums, int index) {
         if (index >= nums.length) {
             return 0;
         }
+        int recurse = array11(nums, index + 1);
         if (nums[index] == 11) {
-            return 1 + array11(nums, index + 1);
+            return recurse + 1;
         } else {
-            return array11(nums, index + 1);
+            return recurse;
         }
     }
 
diff --git a/ch08/Examples.java b/ch08/Examples.java
@@ -1,19 +1,4 @@
-public class Recursion {
-
-    public static void main(String[] args) {
-        System.out.println("countdown");
-        countdown(3);
-
-        System.out.println("nLines");
-        nLines(3);
-
-        System.out.println("countup");
-        countup(3);
-
-        System.out.println("displayBinary");
-        displayBinary(23);
-        System.out.println();
-    }
+public class Examples {
 
     public static void countdown(int n) {
         if (n == 0) {
@@ -24,10 +9,6 @@ public static void countdown(int n) {
         }
     }
 
-    public static void newLine() {
-        System.out.println();
-    }
-
     public static void nLines(int n) {
         if (n > 0) {
             System.out.println();
@@ -56,4 +37,21 @@ public static void displayBinary(int value) {
         }
     }
 
+    public static void main(String[] args) {
+        System.out.println("countdown");
+        countdown(3);
+
+        System.out.println("nLines");
+        nLines(3);
+
+        // forever("Ha!");
+
+        System.out.println("countup");
+        countup(3);
+
+        System.out.println("displayBinary");
+        displayBinary(23);
+        System.out.println();
+    }
+
 }
diff --git a/ch08/Series.java b/ch08/Series.java
@@ -1,6 +1,3 @@
-/**
- * Examples from Chapter 8.
- */
 public class Series {
 
     public static int factorial(int n) {
