H:MM:SS. Minutes and seconds always take two digits; hours take as many digits as they need and can go past 23.For example, for the input 3725 the program prints 1:02:05.
Hint: integer division (/) and the remainder (%) do most of the work, and System.out.printf with %02d pads a number with zeros to two digits.
static int maxOfThree(int a, int b, int c) that returns the largest of its three arguments. Don't use Math.max.]]>static boolean isLeapYear(int year) that returns true if year is a leap year in the Gregorian calendar and false otherwise. A year is a leap year when it is divisible by 4, except that years divisible by 100 are leap years only if they are also divisible by 400. So 2024 and 2000 are leap years, but 2023 and 1900 are not. You can assume that year ≥ 1.]]>static void printStaircase(int n) that prints a staircase of asterisks n lines tall, aligned to the right: line i (counting from 1) has n − i spaces followed by i asterisks. For n = 0 it prints nothing. The method prints the staircase; it doesn't return anything.For example, printStaircase(4) prints:
* ** *** ****]]>
static double toFahrenheit(double celsius) returns the temperature in degrees Fahrenheit, using F = C × 9 / 5 + 32;static double toCelsius(double fahrenheit) does the opposite conversion, using C = (F − 32) × 5 / 9.The tests print each result rounded to two decimal places, so 100 °C is checked as 212.00. Remember that in Java dividing one int by another gives an int: 9 / 5 is 1.
a and b:static int gcd(int a, int b) returns their greatest common divisor (GCD), the largest integer that divides both;static int lcm(int a, int b) returns their least common multiple (LCM), the smallest positive integer that is a multiple of both. Write it by calling gcd: LCM(a, b) = a / GCD(a, b) × b.For example, gcd(12, 18) is 6 and lcm(12, 18) is 36. The tests only use values whose LCM fits in an int.
Euclid's algorithm finds the GCD quickly: while b is not 0, replace (a, b) with (b, a % b); then a is the answer.
]]>static String initials(String name) that returns the first letter of every word in name, in upper case, joined together. Words are separated by one or more spaces, and name can also start or end with spaces. If name has no words at all, return the empty string.For example, initials("ada lovelace") returns "AL".
static boolean isPalindrome(String text) that returns true if text is a palindrome once you ignore the difference between upper and lower case and skip every character that is not a letter or a digit (spaces, punctuation and so on), and false otherwise. A text with no letters or digits, such as the empty string, counts as a palindrome.For example, "Radar" and "Never odd or even" are palindromes, but "Java" is not. Character.isLetterOrDigit and Character.toLowerCase will help.
static int indexOfMax(int[] values) that returns the index of the largest value in the array values. If the largest value appears more than once, return the smallest of its indexes (the first place it appears). If the array is empty, return -1. The values can be negative.For example, for {4, 9, 2, 9} the method returns 1.
For example, for the input 4 8 6 2 the average is 5, so the program prints 8 6.
You don't know in advance how many numbers there are, so keep them in an ArrayList<Integer>. The Scanner method hasNextInt() tells you whether there is another integer to read.
static String mostFrequentWord(String text) that returns the word that appears most often in text. If several words share the highest count, return the one that appears first in text. text holds at least one word; words are separated by single spaces, with no spaces at the start or end, and are compared exactly as written ("Sol" and "sol" are different words).For example, mostFrequentWord("do re mi do") returns "do".
Count the words with a HashMap<String, Integer>. CodeRunner puts your method inside a class of its own, so there is nowhere to write an import: use the full name, java.util.HashMap.
BankAccount that keeps a balance in whole units of money. It has:BankAccount(int initialBalance), where initialBalance ≥ 0;int getBalance(), which returns the current balance;void deposit(int amount), which adds amount to the balance, but does nothing if amount is zero or negative;boolean withdraw(int amount), which takes amount out of the balance and returns true. If amount is zero, negative or more than the balance, it leaves the balance as it is and returns false.Keep the balance in a private field, so the only way to change it is through these methods. Each account has its own balance.
Fraction for fractions of integers, always kept in lowest terms with a positive denominator. It has:Fraction(int numerator, int denominator), where denominator is never 0. It stores the fraction in lowest terms with the sign in the numerator: new Fraction(6, -8) stores −3/4, and any fraction equal to zero is stored as 0/1;int getNumerator() and int getDenominator();Fraction plus(Fraction other) and Fraction times(Fraction other), which return a new Fraction holding the sum or the product and leave both fractions unchanged;String toString(), which returns the numerator, a slash and the denominator, such as "-3/4", "5/1" or "0/1".The tests use small numbers, so every result fits in an int. Hint: to reduce a fraction, divide the numerator and the denominator by their greatest common divisor.
Write a recursive method static void hanoi(int n, char from, char to, char spare) that prints the moves of the shortest solution for moving n disks from peg from to peg to, with spare as the third peg. Print one move per line: the peg the disk leaves, a space, ->, a space and the peg it goes to, as in A -> C. For n = 0 the method prints nothing.
For example, hanoi(2, 'A', 'C', 'B') prints:
A -> B A -> C B -> C
Hint: before the largest disk can move, where must the other n − 1 disks be?
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