This project is a small showcase for what can be done in Kotlin with small algorithms. The aim of this exercises are to solve the problems using kotlin library, therefore the idea is to make it as simple as possible. For each one please check the respective unit test.
Write a function to calculate the factorial for a given number.
The factorial of a positive number n is given by:
factorial of n (n!) = 1 * 2 * 3 * 4 * ... * n
An Armstrong number is the one that equals the sum of its digits raised to the power of the number of digits in that number which is to be checked. To be more clear, let the number be n and the number of digits be x. We represent the number as nx nx-1 nx-2...n3 n2 n1 where n1, n2, n3...nx are single digits 0-9. n is an Armstrong number if
(n1)^x + (n2)^x + (n3)^x + (nx-1)^x + (nx)^x = n
153, 371, 9474 and 54748 are few Armstrong numbers.
153 = 1^3 + 5^3 + 3^3371 = 3^3 +7^3 +1^39474 = 9^4 + 4^4 +7^4 + 4^454748 = 5^5 + 4^5 + 7^5 + 4^5 + 8^5
In mathematics, the Fibonacci numbers or Fibonacci series or Fibonacci sequence are the numbers in the following integer sequence:
0 1 1 2 3 5 8 13 21 34 55 89 144 233 377, ...
By definition, the first two numbers in the Fibonacci sequence are 0 and 1, and each subsequent number is the sum of the previous two.
Write some code that prints out the following for a contiguous range of numbers:
the number 'fizz' for numbers that are multiples of 3, 'buzz' for numbers that are multiples of 5, 'fizzbuzz' for numbers that are multiples of 15, e.g. if I run the program over a range from 1-20 I should get the following output: 1 2 fizz 4 buzz fizz 7 8 fizz buzz 11 fizz 13 14 fizzbuzz 16 17 fizz 19 buzz.
Create a Password verifications class called PasswordVerifier.
- Add the following verifications to a master function called
verify()- password should be larger than 8 chars
- password should not be null
- password should have one uppercase letter at least
- password should have one lowercase letter at least
- password should have one number at least
Each one of these should throw an exception with a different message of your choosing.
A prime number (or a prime) is a natural number greater than 1 that has no positive divisors other than 1 and itself.
A natural number greater than 1 that is not a prime number is called a composite number. For example, 5 is prime, as only 1 and 5 divide it, whereas 6 is composite, since it has the divisors 2 and 3 in addition to 1 and 6.
The fundamental theorem of arithmetic establishes the central role of primes in number theory: any integer greater than 1 can be expressed as a product of primes that is unique up to ordering. This theorem requires excluding 1 as a prime.
Write function that translates a text to Pig Latin and back. English is translated to Pig Latin by taking the first letter of every word, moving it to the end of the word and adding ‘ay’. “The quick brown fox” becomes “Hetay uickqay rownbay oxfay”.
Write a program that automatically converts English text to Morse code and vice versa.
Collection of string a list exercises.
- Write a function that takes a number and returns a list of its digits. So for
2342it should return[2, 3, 4, 2]. - Write a function that tests whether a string is a palindrome. A palindrome is a word, number, phrase, or other sequence of characters which reads the same backward as forward, such as madam or racecar or the number 10801.
- Write a function that takes a list of strings and retrieves them, one per line, in a rectangular frame. For example the list
["Hello", "World", "in", "a", "frame"]gets returned as:
*********
* Hello *
* World *
* in *
* a *
* frame *
*********