How to Calculate Age Range Compatibility as an Equation in Java
The challenge
Everybody knows the classic “half your age plus seven” dating rule that a lot of people follow (including myself). …
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342 articles about java development, tools, and best practices
How to Find the Longest Mountain in Array in Java
The challenge
Let’s call any (contiguous) subarray B (of A) a mountain if the following properties hold:
B.length >= 3- There exists some
0 …
How to Solve the “Decode a String” Challenge in Java
The challenge
Given an encoded string, return its decoded string.
The encoding rule is: k[encoded_string], where the encoded_string inside the square …
How to Find the Maximum Difference Between Node and Ancestor in Java
The challenge
Given the root of a binary tree, find the maximum value V for which there exist different nodes A and B where V = |A.val - B.val| and A …
How to Find the Integral using Java
The challenge
Create a function that finds the integral of the expression passed.
In order to find the integral all you need to do is add one to the …
Read Article →How to Build Strings from a Size in Java
The challenge
Write a function stringy that takes a size and returns a string of alternating '1s' and '0s'.
The string should start with a 1.
A string …
Read Article →Best Time to Buy and Sell Stock in Java
The challenge
Say you have an array for which the ith element is the price of a given stock on day i.
If you were only permitted to complete at most …
Read Article →How to Solve the “To square(root) or not to square(root)” Challenge in Java
The challenge
Write a method, that will get an integer array as parameter and will process every number from this array.
Return a new array with …
Solving the Rule of Divisibility by 13 in Java
The challenge
wikipedia.com
When you divide the successive powers of 10 by 13 you get the following remainders of the integer divisions:
1, 10, 9, …
How to Calculate Buddy Strings in Java
The challenge
Given two strings A and B of lowercase letters, return true if you can swap two letters in A so the result is equal to B, otherwise, …
How to Flip a Binary Matrix in Java
The challenge
Given a binary matrix A, we want to flip the image horizontally, then invert it, and return the resulting image.
To flip an image …
Read Article →How to Tilt a Binary Tree in Java
The challenge
Given the root of a binary tree, return the sum of every tree node’s tilt.
The tilt of a tree node is the absolute difference …
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