Java

Decimal to Factorial and Back in Java

February 5, 2021 #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 …

Vowel Count in Java

February 4, 2021 #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 …

Equal Sides Of An Array in Java

February 3, 2021 #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 …

Largest 5 digit number in a series in Java

February 2, 2021 #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: …

Next smaller number with the same digits in Java

February 1, 2021 #Java

The challenge

Write a function that takes a positive integer and returns the next smaller positive integer containing the same digits.

For example: …

Count of positives / sum of negatives in Java

January 31, 2021 #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 …

Find the stray number in Java

January 30, 2021 #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 …

4 By 4 Skyscrapers in Java

January 29, 2021 #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

January 28, 2021 #Java #Maven

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 …

Sum by Factors in Java

January 26, 2021 #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 …

Count the divisors of a number in Java

January 25, 2021 #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

January 24, 2021 #Java

The challenge

Inspired from real-world Brainf**k, we want to create an interpreter of that language which will support the following instructions: …