size ArrayList numbers = new ArrayList<>(); numbers.add(10); numbers.add(5); System.out.println(numbers.size()); //2 for(int i=0; i<5; i++) { numbers.add(i); } System.out.println(numbers); //[10, 5, 0, 1, 2, 3, 4] int len = numbers.size(); System.out.println(len); //7 Program outputs: 2 [10, 5, 0, 1, 2, 3, 4] 7 ================================== i numbers = new ArrayList<>(); numbers.add(10); numbers.add(5); numbers.add(6); numbers.add(22); numbers.add(-4); System.out.println(numbers); //[10, 5, 6, 22, -4] for (int i=0; i numbers = new ArrayList<>(); numbers.add(10); numbers.add(5); numbers.add(6); numbers.add(22); numbers.add(-4); for (int number : numbers) { System.out.println(number); } Program outputs: 10 5 6 22 -4 ================================== SUM length of ALL words ArrayList words = new ArrayList<>(); words.add("Lake"); words.add("Swamp"); words.add("Hoe"); words.add("Shovel"); int length = 0; for (String word : words ) { length = length + word.length(); } System.out.println("Combined length: " + length ); Program outputs: Combined length: 19