For challenges about rearranging a set of mathematical operators or numbers to fulfill a certain expression.

This tag is for challenges about expression-building, that is, challenges where you are given a list of numbers and/or operators, and you must rearrange them into a certain expression. This is a somewhat broad description, so here are some examples of tasks that fall under expression-building:

  • Given a list of arithmetic operators (+, -, =, etc.), insert digits between them so that the resulting expression is true. (example)

  • Use the number four plus some operations to calculate any other number. (example)

  • Given a list of numbers, insert operators between them to make an expression that evaluates to some other number. (example

There are many other related tasks that could fall under expression-building too. These are just examples.