Use a loop to calculate the area of the closed figure There are easy ways to do this with a list of coordinates of a polygon. One with a description and example of the process is at wikihow. Do this using a loop, with any additional code needed to handle the first or last points, as needed. Note that figures drawn in the opposite direction assumed in a particular method may result in negative areas. Use that knowledge to determine if the user drew the figure clockwise or counterclockwise.