Averages of numbers in Java
The challenge
Get the averages of these numbers
Write a method, that gets an array of integer-numbers and return an array of the averages of each …
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Decimal to Factorial and Back in Java
The challenge
Coding decimal numbers with factorials is a way of writing out numbers in a base system that depends on factorials, rather than powers …
Read Article →Vowel Count in Java
The challenge
Return the number (count) of vowels in the given string.
We will consider a, e, i, o, u as vowels for this challenge (but not y).
The …
Read Article →Equal Sides Of An Array in Java
The challenge
You are going to be given an array of integers. Your job is to take that array and find an index N where the sum of the integers to the …
Read Article →Largest 5 digit number in a series in Java
The challenge
In the following 6 digit number:
283910
91 is the greatest sequence of 2 consecutive digits.
In the following 10 digit number: …
Read Article →Next smaller number with the same digits in Java
The challenge
Write a function that takes a positive integer and returns the next smaller positive integer containing the same digits.
For example: …
Read Article →Count of positives / sum of negatives in Java
The challenge
Given an array of integers.
Return an array, where the first element is the count of positives numbers and the second element is sum of …
Read Article →Find the stray number in Java
The challenge
You are given an odd-length array of integers, in which all of them are the same, except for one single number.
Complete the method …
Read Article →4 By 4 Skyscrapers in Java
The challenge
In a grid of 4 by 4 squares you want to place a skyscraper in each square with only some clues:
- The height of the skyscrapers is …
How to Fix: package org.junit.jupiter.api does not exist
The problem
If you have received the package org.junit.jupiter.api deos not exist error when trying to run a JUnit Java Test with Maven, it’s …
How to Programmatically Filter ag-Grid Columns in Angular
You can easily control the column filtering in ag-Grid by using the getFilterInstance and setModel methods associated to the column you need …
Sum by Factors in Java
The challenge
Given an array of positive or negative integers
I= [i<sub>1</sub>,..,i<sub>n</sub>]
you have to produce a sorted …
Read Article →Count the divisors of a number in Java
The challenge
Count the number of divisors of a positive integer n.
Random tests go up to n = 500000.
Examples
numberOfDivisors(4) == 3 // 1, 2, 4 …My smallest code interpreter in Java
The challenge
Inspired from real-world Brainf**k, we want to create an interpreter of that language which will support the following instructions: …
Read Article →Pick peaks in Java
The challenge
Write a function that returns the positions and the values of the “peaks” (or local maxima) of a numeric array.
For example, …
Read Article →Number of trailing zeros of N in Java
The challenge
Write a program that will calculate the number of trailing zeros in a factorial of a given number.
N! = 1 * 2 * 3 * ... * N
Be careful …
Read Article →Alphabetic Anagrams in Java
The challenge
Consider a “word” as any sequence of capital letters A-Z (not limited to just “dictionary words”). For any word …
Read Article →Remove file from Git without deleting locally
If you find yourself in a position where you have already committed some files to git, and they are in the remote repository already, but you want to …
Read Article →Recover a secret string from random triplets in Java
The challenge
There is a secret string which is unknown to you. Given a collection of random triplets from the string, recover the original string.
A …
Read Article →Range Extraction in Java
The challenge
A format for expressing an ordered list of integers is to use a comma separated list of either
- individual integers
- or a range of …
Reversed Words in Java
The challenge
Complete the solution so that it reverses all of the words within the string passed in.
Example:
ReverseWords.reverseWords("The …CamelCase Method in Java
The challenge
Write a simple CamelCase method for strings.
All words must have their first letter capitalized without spaces.
Example:
// …Even or Odd in Java
The challenge
Create a function that takes an integer as an argument and returns “Even” for even numbers or “Odd” for odd …
Read Article →Square Every Digit in Java
The challenge
You need to square every digit of a number and concatenate them.
For example, if we run 9119 through the function, 811181 will come out, …
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