Frequently asked puzzles during interview

This is a collection of some good interview puzzles which either i have faced or heard from friends.

1.) Burning rope/wood - measure time without clock

2.) Nine(x) ball problem

3.) Crossing the bridge puzzle

4.) 100-coin puzzle

5.) Mislabeled jar - Jelly Beans problem

6.) Red-Blue marble - probability puzzle

7.) Measure "4 liter water" problem

8.) 25 horse, 5 tracks, find 3 fastest horses

9.) Two egg puzzle

10.) Find the celebrity in the party

11.) Find black/white pair of sock

12.) Two door, which path leads to heaven?

13.) 100 door puzzle

14.) Ant and triangle problem

15.) King and wine problem

16.) Gold bar distribution problem

17.) Inverted card puzzle

18.) Pirates profit distribution problem

List updating continuously... :)