lecture code for jan 31

Author: joshHug

lec4_lists2/SLList.java

@@ -16,12 +16,6 @@ public IntNode(int i, IntNode n) {
     private IntNode sentinel;
     private int size;
 
-    public SLList(int x) {
-        sentinel = new IntNode(12873, null);
-        sentinel.next = new IntNode(x, null);
-        size = 1;
-    }
-
     public SLList() {
         size = 0;
         sentinel = new IntNode(12873, null);

lec5_lists3/SLList.java

@@ -0,0 +1,50 @@
+package lec5_lists3;
+
+/* List of anythings */
+public class SLList<Mustard> {
+    private class MustardNode {
+        public Mustard item;    // first number in the list
+        public MustardNode next; // rest of the list
+
+        public MustardNode(Mustard i, MustardNode n) {
+            item = i;
+            next = n;
+        }
+    }
+
+
+    // the sentinel node is the dummy node at th front of the list
+    // and the real first item is sentinel.next (if it exists)
+    private MustardNode sentinel;
+    private int size;
+
+    public SLList() {
+        size = 0;
+        sentinel = new MustardNode(null, null);
+    }
+
+    public void addFirst(Mustard x) {
+        size += 1;
+        sentinel.next = new MustardNode(x, sentinel.next);
+    }
+
+    public Mustard getFirst() {
+        return sentinel.next.item;
+    }
+
+    public void addLast(Mustard x) {
+        size += 1;
+        MustardNode p = sentinel;
+
+        // advance p until it is the last item
+        while (p.next != null) {
+            p = p.next;
+        }
+
+        p.next = new MustardNode(x, null);
+    }
+
+    public int size() {
+        return size;
+    }
+}

lec5_lists3/SLListUser.java

@@ -0,0 +1,15 @@
+package lec5_lists3;
+
+public class SLListUser {
+    public static void main(String[] args) {
+        SLList<String> L = new SLList<>();
+        L.addFirst("mustard");
+        L.addFirst("mustard2");
+        L.addLast("mustard");
+        L.addLast("ketchup");
+        L.addLast("dijon");
+
+        System.out.println(L.size());
+        int[] z = {9, 10, 11, 12, 13};
+    }
+}