1799 Yeehaa! (1)
1401 Factorial (1)
1654 Area (3)
2309 BST (3)
2693 Chocolate Chip Cookies (4)
Note: Given two points, how do you find a circle with a fixed radius that goes through the two points?
Hint: The answer for is quite big.
2085 Inversion (5)
2356 Find a multiple (7, challenge problem)
1148 Utopia Divided (9, challenge problem)
Hint: Solve the 1-dimensional version of the problem first.