Thursday is code puzzler day here at DZone. The idea is simple: solve the coding problem as efficiently as you can, in any language or framework that you find suitable.
Note: Even though there really is nothing stopping you from finding a solution to this on the internet, try to keep honest, and come up with your own answer. It's all about the participation!
Do you have code puzzlers that you'd like to share with the DZone community? If so, please submit here.
Efficient Duplicate Detection
Give an array of 1001 elements, which includes the numbers 1 to 1000 inclusive in random order, plus one duplicate number, write the most efficient algorithm to detect the duplicate number. Make sure you only access each item in the array a maximum of once.
Catch up on all our previous puzzlers here.