Once upon a time there was a girl named Goldilogs. As she was walking through the woods one day, she came upon a curious, long house. Walking all round it and seeing no one at home, she tried the door and found that it was open. Inside, she saw a very long row of chairs. She tried sitting in the first chair, but it was too small for her. So she tried sitting in the second chair, but it was also too small. The third chair was too small as well. “Oh dear,” said Goldilogs. “This is going to take all day.”

But then Goldilogs noticed that the chairs were arranged in order, from smallest to largest, and she clapped her hands with delight. “What organized people must live here!” she exclaimed. “I wonder, how ever did they arrange their chairs this way?” So she tried the chair in the middle of the row, and it was too big. Next she tried the chair a quarter of the way along, and it was too small. She continued in this manner, eliminating half of the remaining chairs with each test, until finally she found one that was Just Right. In fact, she found it so quickly that she had plenty of time to sit and enjoy reading from the selection of algorithms textbooks that she found on a shelf, and then she put everything back the way she found it and left before the bears got home.