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--- j1-3_loops [2024/12/03 00:35] – created appledog
+++ j1-3_loops [2024/12/03 00:42] (current) – appledog
@@ Line 130: / Line 130: @@
 }
 </Code>
+Although most loops by convention start at 0 and use something like i < 3, it's the same thing. These loops are the same as C loops more or less.
+== for-each
+Java has for-each which is used for arrays, lists, and so on.
+<Code:Java>
+public class Main {
+    public static void main(String[] args) {
+        int[] numbers = {10, 20, 30, 40, 50};
+        for (int num : numbers) { // Iterates over each element in the array
+            System.out.println("Number: " + num);
+        }
+    }
+}
+</Code>
+As you can see, this is a great way to iterate through lists.
+== iterators
+Sometimes the reason why you want to for-each is to remove bad elements from a list. If you have a lot of memory you can just build a new list and delete the old one. But you can also use iterators, and that will let you remove items in-place. Otherwise they are pretty much equivalent in terms of looping through a list.
+<Code:Java>
+import java.util.ArrayList;
+import java.util.Iterator;
+public class Main {
+    public static void main(String[] args) {
+        ArrayList<String> list = new ArrayList<>();
+        list.add("Apple");
+        list.add("Banana");
+        list.add("Cherry");
+        Iterator<String> iterator = list.iterator();
+        while (iterator.hasNext()) {
+            System.out.println(iterator.next());
+        }
+    }
+}
+</Code>