I think that this is the best of my collection. It takes great innovation to crack this one.

You have a rose garden. You have planted 16 rose plants in a circle. Some of them are red and some are white. These plants are somwhat strange. They flower according to the following rules:
1. Each plant has a new flower everyday.
2. Each plant bears only one flower on any day.
3. The color of the flower on a plant depends upon the colors of its neighbours' flowers on previous day. If both the neighbours had same color on previous day then the plant has red flower and if the neighbours had different colors then the plant has white rose.

After many days you spot that all the roses have become red. But you want both colors to live. So you start with a different initial arrangement. But to your disappointment, you again find that after sufficient number of days, all the flowers have turned red. You are smart enough to deduce that given any initial arrangement, you always end up with all red flowers. What I want to see is whether you are smart enough to find out why this happens and for which numbers other than 16, the same thing happens.

Click here for answer.


Back to main page