You are given a set of positive integers. You must arrange them into pairs such that: Each pair contains 2 numbers, one of which is a multiple of another. For example, 8 is a multiple of 4, and 9 is a multiple of 9. If the same number occurs many times in the initial set, it can be used that ma...

Convert hexadecimal to decimal code-golf base-conversion We have a lot of base conversion challenges. Surprisingly, aside from one closed challenge, there aren't any where the goal is purely to convert hexadecimal to decimal. This is different from challenges like converting hexadecimal to binary...

This code-golf challenge will give you two positive integers n and k as inputs and have you count the number of rectangles with integer coordinates that can be drawn with vertices touching all four sides of the \$n \times k\$ rectangle $$ \{(x,y) : 0 \leq x \leq n, 0 \leq y \leq k\}. $$ That is, ...