What is the best c++ program to offer for my teacher?

Question

Hello guys, I need a useful program where I can only use if-else, switch, and looping. Anyone? If you can't share any codes, please share some ideas. I really need it for my grades. :) Let's be friends in Facebook, if you want.
~Myan Jeon Kim~

Answer 1

A command line calculator is a classic example

Answer 2

The rock paper scissor game is a classic too

Answer 3

a program to solve aX^2+bX+c=0, for a given a, b, c

Answer 4

A program that counts words in a text document.