How to Reverse a Number in Java
The challenge
Given a number, write a function to output its reverse digits. (e.g. given 123 the answer is 321)
Numbers should preserve their sign; …
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Positions Average in Java
The challenge
Suppose you have 4 numbers: '0', '9', '6', '4' and 3 strings composed with them:
s1 = "6900690040"
s2 = "4690606946"
s3 …Determine the Date by the Day Number in Java
The challenge
What date corresponds to the nth day of the year?
The answer depends on whether the year is a leap year or not.
Write a function that …
Read Article →Correct the time-string in Java
The challenge
- You have to create a method, that corrects a given time string.
- There was a problem in addition, so many of the time strings are …
Shifter Words Challenge in Java
The challenge
You probably know that some characters written on a piece of paper, after turning this sheet 180 degrees, can be read, although …
Read Article →Find Maximum and Minimum Values of a List in Java
The challenge
Make two functions, max and min that take a(n) array/vector of integers list as input and outputs, respectively, the largest and lowest …
Valid Parentheses in Java
The challenge
Write a function that takes a string of parentheses, and determines if the order of the parentheses is valid. The function should return …
Read Article →Boggle Word Checker in Java
The challenge
Write a function that determines whether a string is a valid guess in a Boggle board, as per the rules of Boggle. A Boggle board is a 2D …
Read Article →Reverse the bits in an integer in Java
The challenge
Write a function that reverses the bits in an integer.
For example, the number 417 is 110100001 in binary. Reversing the binary is …
Spring Boot no main manifest attribute, in
You have created a ./target/.jar and have tried to run it using java -jar <app>.jar yet receive a spring boot no main manifest attribute, in …
Matrix Addition in Java
The challenge
Write a function that accepts two square matrices (N x N two dimensional arrays), and return the sum of the two. Both matrices being …
Numbers that are a power of their sum of digits in Java
The challenge
The number 81 has a special property, a certain power of the sum of its digits is equal to 81 (nine squared). Eighty one (81), is the …
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