update lecture 3 code:

Author: joshHug

lec3_intro3/IntList.java

@@ -1,37 +1,50 @@
 package lec3_intro3;
 
+/* An infinitely long list of integers. */
 public class IntList {
-    public int first;
-    public IntList rest;
+    public int first;    // first number in the list
+    public IntList rest; // rest of the list
 
     public IntList(int f, IntList r) {
         first = f;
         rest = r;
     }
 
+    /** return the number of items in the list. */
     public int size() {
-        if (rest == null) {
+        if (this.rest == null) {
+            // professor what row am I in?
             return 1;
         }
-        return 1 + rest.size();
+        return 1 + this.rest.size();
     }
 
+    // get the size of the list with iteration
     public int iterativeSize() {
-        IntList p = this;
         int totalSize = 0;
+        IntList p = this;
         while (p != null) {
             totalSize += 1;
             p = p.rest;
         }
         return totalSize;
     }
 
+    public int get(int i) {
+        if (i == 0) {
+            return this.first;
+        }
+        return this.rest.get(i - 1);
+    }
 
     public static void main(String[] args) {
         IntList L = new IntList(15, null);
         L = new IntList(10, L);
         L = new IntList(5, L);
 
+        System.out.println(L.size());
         System.out.println(L.iterativeSize());
+
+        System.out.println(L.get(1));
     }
-}
+}

lec3_intro3/exercises/ExtraIntListPractice.java

@@ -1,43 +0,0 @@
-package lec3_intro3.exercises;
-import lec3_intro3.IntList;
-
-public class ExtraIntListPractice {
-    /** Returns an IntList identical to L, but with
-     * each element incremented by x. L is not allowed
-     * to change. */
-    public static IntList incrList(IntList L, int x) {
-        //TODO fill in code
-        return null;
-    }
-
-    /** Returns an IntList identical to L, but with
-     * each element incremented by x. Not allowed to use
-     * the 'new' keyword. */
-    public static IntList dincrList(IntList L, int x) {
-        // TODO fill in code
-        return null;
-    }
-
-    public static void main(String[] args) {
-        IntList L = new IntList(5, null);
-        L.rest = new IntList(7, null);
-        L.rest.rest = new IntList(9, null);
-
-        System.out.println(L.size());
-        System.out.println(L.iterativeSize());
-
-        // Test your answers by uncommenting.
-        // System.out.println(L.get(1));
-        IntList listPlus3 = dincrList(L, 3);
-        for (IntList p = listPlus3; p != null; p = p.rest) {
-            System.out.print(p.first + ", ");
-        }
-        System.out.println();
-
-        incrList(L, 4);
-        for (IntList p = L; p != null; p = p.rest) {
-            System.out.println(p.first + ", ");
-        }
-        System.out.println();
-    }
-}