A king had received a gift of 100 bottles of wine but suspected one had been poisoned.
The king placed 100 wine bottles on the table, 99 of which contained normal wine and one which contained poison. Even a sip of the poisoned wine was enough to kill.
The poison was indetectable, meaning it wouldn’t alter the taste or smell of the wine. Each of the king’s knights could bring as many of their own slaves as they wished to help them in the task.
The catch was that the poison took effect exactly 24 hours after consumption. Thus, the knights had 24 hours to identify the poisoned bottle.
How could the knights determine which bottle of wine is poisoned within the time frame?
You need 7 slaves. You line up the bottles 1 to 100. You assign a 7-digit binary number to each bottle (e.g., Bottle 1 is 0000001, Bottle 100 is 1100100).
- Slave 1 takes a sip from every bottle that has a 1 in the first binary column.
- Slave 2 takes a sip from every bottle that has a 1 in the second binary column.
- And so on…
After 24 hours, look at who died. If Slaves 1, 5, and 7 die, you write a 1 for their spots and a 0 for the survivors. That binary number matches the specific bottle number.
