Araf

Araf is a region based logic puzzle where the grid is divided up into smaller regions.

Rules
The objective is to divide the whole grid into smaller regions, subject to the following rules:
 * 1) Every cell should be contained within a region, and each region should contain two numbers.
 * 2) The area of the region must be between the values of the two numbers.

Example
A standard 10x10 araf and its solution.