From c3826ab8cf38c834e9ef1606e44990bcae5156f1 Mon Sep 17 00:00:00 2001
From: Adam Blank <blank@caltech.edu>
Date: Fri, 14 Jan 2022 17:33:37 +0000
Subject: [PATCH] Add new file
---
04/OurArrayIntList.java | 87 +++++++++++++++++++++++++++++++++++++++++
1 file changed, 87 insertions(+)
create mode 100644 04/OurArrayIntList.java
diff --git a/04/OurArrayIntList.java b/04/OurArrayIntList.java
new file mode 100644
index 0000000..60ded47
--- /dev/null
+++ b/04/OurArrayIntList.java
@@ -0,0 +1,87 @@
+public class OurArrayList<E> implements IList<E> {
+ private E[] data;
+ private int size;
+
+ public OurArrayList(int initialCapacity) {
+ this.data = (E[])new Object[initialCapacity];
+ this.size = 0;
+ }
+
+ public OurArrayList() {
+ this(10);
+ }
+
+ public String toString() {
+ if (this.size == 0) {
+ return "[]";
+ }
+ String result = "[";
+ for (int i = 0; i < this.size; i++) {
+ result += this.data[i] + ", ";
+ }
+ result = result.substring(0, result.length() - 2);
+ return result + "]";
+ }
+
+ public void add(E element) {
+ this.add(this.size, element);
+ }
+
+ /**
+ * Puts element at index idx, shifting over everything after to the right.
+ * @param idx
+ * @param element
+ * For example, idx = 2, element = 42
+ * [1, 2, 3, 4, 5]
+ * ^
+ * [1, 2, 42, 3, 4, 5]
+ */
+ public void add(int idx, E element) {
+ resize();
+ for (int i = this.size; i > idx; i--) {
+ this.data[i] = this.data[i-1];
+ }
+ this.data[idx] = element;
+ this.size++;
+ }
+
+ private void resize() {
+ // size vs. capacity < how much storage space in the list
+ // ^ how many elements in the list
+ // capacity == this.data.length
+ if (this.size == this.data.length) {
+ // Time to resize!
+ E[] newData = (E[])new Object[this.data.length * 2];
+ for (int i = 0; i < this.size; i++) {
+ newData[i] = this.data[i];
+ }
+ this.data = newData;
+ }
+ }
+
+ @Override
+ public int size() {
+ return this.size;
+ }
+
+ @Override
+ public void set(int idx, E elem) {
+ if (idx < 0 || idx >= this.size) {
+ throw new IllegalArgumentException(idx + " is not a valid index!");
+ }
+ this.data[idx] = elem;
+
+ }
+
+ public E get(int idx) {
+ if (idx < 0 || idx >= this.size) {
+ throw new IllegalArgumentException(idx + " is not a valid index!");
+ }
+ return this.data[idx];
+ }
+
+ @Override
+ public void clear() {
+ this.size = 0;
+ }
+}
--
GitLab