18. User paint. Write a program, userpaint.m, which asks the user for the dimensions on the room to be painted, the dimensions of the windows in the room, the number of windows, the dimensions of door openings in the room, and the number of door openings. Compute the number of gallons of paint needed to paint the room, assuming a gallon of paint covers 400 square feet, and report the result to the user. Personalize the program by asking the user for a first name, and report the results with a greeting using the first name