Create an ArrayList that stores the integers 5, 8, 14, 18, 24, 39, and 56 and only print the numbers that are divisible by 3.
import java.util.ArrayList;
public class DivisibleBy3 {
public static void main(String[] args) {
ArrayList<Integer> numbers = new ArrayList<>(Arrays.asList(5, 8, 14, 18, 24 ,39, 56));
for (int number : numbers) {
if (number % 3 == 0) {
System.out.println(number);
}
}
}
}
DivisibleBy3.main(null);
Finish the code below so that all duplicates in the ArrayList are removed.
import java.util.Arraylist;
public class RemoveDuplicates {
public static void main(String[] args) {
ArrayList<Integer> arr = new ArrayList<>(); // creating new arraylist of integers
// adding integers to the arraylist
arr.add(1);
arr.add(7);
arr.add(9);
arr.add(13);
arr.add(3);
arr.add(7);
arr.add(9);
arr.add(2);
// add your code here
for(int i = 0: i < arr.size(): i++) {
for (int j = i + 1; j < arr.size(): j++) {
if(arr.get(i).equals(arr.get(j))) {
arr.remove(j);
j--;
}
}
}
System.out.println(arr);
}
}
RemoveDuplicates.main(null);
Traverse the following ArrayList using a loop. Remove each element that is a multiple of 4.
public static void main(String[] args)
{
ArrayList<Integer> arr = new ArrayList<>();
arr.add(1);
arr.add(7);
arr.add(9);
arr.add(80);
arr.add(13);
arr.add(3);
arr.add(7);
arr.add(8);
arr.add(2);
arr.add(16);
for(int i = 0; i < arr.size(); i++) {
if(arr.get(i) % 4 == 0) {
arr.remove(i);
}
}
}
main(null);
Find the maximum, minimum, and sum of an ArrayList.
public static void main(String[] args)
{
ArrayList<Integer> arr = new ArrayList<>();
arr.add(1);
arr.add(7);
arr.add(9);
arr.add(80);
arr.add(13);
arr.add(3);
arr.add(7);
arr.add(8);
arr.add(2);
arr.add(16);
int max = Integer.MIN_VALUE; // initialize max
int min = Integer.MAX_VALUE; // initialize min
int sum = 0; // initialize sum
for (int num : arr) {
if (num > max) {
max = num; // update max if current number is greater
}
if (num < min) {
min = num; // update min if current number is smaller
}
sum += num; // add current number to sum
}
System.out.println("Max: " + max);
System.out.println("Min: " + min);
System.out.println("Sum: " + sum);
}
import java.util.ArrayList;
import java.util.Scanner;
public class FavoriteChip {
public static void main(String[] args) {
ArrayList<String> chipsBag = new ArrayList<>();
Scanner scanner = new Scanner(System.in);
chipsBag.add("BBQ");
chipsBag.add("Cheddar");
chipsBag.add("Salt and Pepper");
System.out.print("Enter your favorite chip flavor: ");
String favoriteFlavor = scanner.nextLine();
// implement your own search logic here
boolean found = false; // track
// Traverse the arraylist
for(int i = 0; i < chipsBag.size(); i++) {
// element is equal to favoriteFlavor
if(chipsBag.get(i).equals(favoriteFlavor)) {
found = true; // break the loop
break;
}
}
if(found) {
System.out.println(favoriteFlavor + " is in the bag!");
} else {
System.out.println(favoriteFlavor + " is not in the bag.");
}
}
}
FavoriteChip.main(null);
Given an ArrayList of String objects, sort the following ArrayLists on ascending order of word length.
import java.util.ArrayList;
public class SortByLength {
public static void main(String[] args) {
ArrayList<String> words = new ArrayList<>(); // creating new arraylist
words.add("theater");
words.add("connection");
words.add("seasonal");
words.add("feast");
words.add("meeting");
// sort the list by length
for (int i = 1; i < words.size(); i++) {
String key = words.get(i);
int j = i - 1;
// moving elements of array
while (j >= 0 && words.get(j).length() > key.length()) {
words.set(j + 1, words.get(j));
j = j - 1;
}
words.set(j + 1, key);
}
System.out.println(words); // print sorted list
}
}
SortByLength.main(null);
import java.util.*;
public class Main {
public static void main(String[] args) {
ArrayList<Integer> list = new ArrayList<>();
list.add(5);
list.add(10);
list.add(15);
System.out.println("Original list: " + list);
// Add an element
list.add(20);
System.out.println("After adding an element: " + list);
// Remove an element
list.remove(new Integer(10));
System.out.println("After removing an element: " + list);
// Set an element
list.set(1, 100);
System.out.println("After setting an element: " + list);
// Get an element
int element = list.get(0);
System.out.println("Got element: " + element);
// Sort the list
Collections.sort(list);
System.out.println("After sorting: " + list);
}
}
You are given an ArrayList of Student objects. Each Student has a name (String) and a GPA (double). Create a program that sorts the Student objects in descending order of GPA.
import java.util.*;
class Student {
String name;
double gpa;
// constructor
public Student(String name, double gpa) {
this.name = name;
this.gpa = gpa;
}
// for pretty printing
@Override
public String toString() {
return "Student{" +
"name='" + name + '\'' +
", gpa=" + gpa +
'}';
}
}
public class Main {
public static void main(String[] args) {
ArrayList<Student> students = new ArrayList<>();
students.add(new Student("Alice", 3.8));
students.add(new Student("Bob", 3.5));
students.add(new Student("Charlie", 3.9));
System.out.println("Before sorting: " + students);
// sort in descending order of GPA
students.sort((s1, s2) -> Double.compare(s2.gpa, s1.gpa));
System.out.println("After sorting: " + students);
}
}