* Write a function to print all of the permutations of a string.
* Implement malloc.
* Write a function to print the Fibonacci numbers.
* Write a function to copy two strings, A and B. The last few bytes of string A overlap the first few bytes of string B. 世界各国第一美女  如何给男朋友打领带
* How would you print out the data in a binary tree, level by level, starting at the top?
2. Applications
* How can computer technology be integrated in an elevator system for a hundred story office building? How do you optimize for availability? How would variation of traffic over a typical work week or floor or time of day affect this?
* How would you redesign an ATM?
* Suppose we wanted to run a microwave oven from the computer. What kind of software would you write to do this?
* How would you design a coffee-machine for an automobile.
3. Thinkers
* How are M&Ms made?
* If you had to learn a new computer language, how would you go about doing it?
* If MS told you we were willing to invest million in a start up of your choice, what business would you start? Why?