Flash cards
Review the key moves
1/3
Core idea
What is the main idea behind Java How To's?
Lesson checks
Practice each idea before moving on
Short Mimo-style checks built from this lesson's code, terms, and sequence.
1Quick choice
Which statement best captures the main point of this lesson?
2Order
Put the learning moves in the order that makes the concept easiest to apply.
- Count Words - Count how many words are in a sentence.
- Add Two Numbers - Add two numbers and print the result.
These examples show how to solve common tasks in Java.
These examples show how to solve common tasks in Java.
Numbers
- Add Two Numbers - Add two numbers and print the result.
- Swap Two Variables - Exchange values between two variables.
- Even or Odd Number - Check if a number is even or odd.
- Reverse a Number - Reverse a number.
- Positive or Negative - Check if a number is positive or negative.
- Square Root - Find the square root of a number.
- Area of Rectangle - Calculate the area of a rectangle.
- Convert Celsius to Fahrenheit - Convert a temperature from Celsius to Fahrenheit.
- Sum of Digits - Add up the digits of a number.
- Armstrong Number - Check Armstrong number.
- Random Number - Generate a random number.
Strings
- Count Words - Count how many words are in a sentence.
- Count Vowels in a String - Count how many vowels are in a string.
- Remove Vowels from a String - Remove vowels from a string.
- Count Digits in a String - Count digits in a string.
- Reverse a String - Reverse the characters in a string.
- Palindrome Check - Check if a string is the same forward and backward.
- Check Anagram Strings - Check if two strings contain the same characters in different order.
- Convert String to Array - Split a string into an array of words.
- Remove Whitespace - Delete spaces, tabs, and newlines from a string.
- Count Character Frequency - Count how many times each character appears in a string.
Arrays
- Sum of Array Elements - Add all the elements in an array.
- Find Array Average - Calculate the average value of array elements.
- Sort an Array - Sort array elements.
- Find Smallest Element - Find the lowest value in an array.
- Find Largest Element - Find the largest value in an array.
- Second Largest Array - Find the second largest value in an array.
- Min and Max in Array - Find the minimum and maximum value in an array.
- Merge Two Arrays - Combine two arrays into one.
- Remove Duplicates - Remove duplicates from an array using a Set.
- Find Duplicates - Find duplicate elements in an array.
- Shuffle an Array - Randomize the order of array elements.
Algorithms
- Factorial of a Number - Find the factorial of a number.
- Fibonacci Sequence - Print the first 10 Fibonacci numbers.
- Find GCD - Find the Greatest Common Divisor (GCD).
- Check Prime Number - Check if a number is prime.
Collections
- ArrayList Loop - Loop through an ArrayList.
- HashMap Loop - Loop through a HashMap.
- Loop Through an Enum - Iterate over enum values.