An algorithm (pronounced AL-go-rith-um) is a list of rules to follow in order to solve a problem.

Algorithms need to have their steps in the right order. Think about an algorithm for getting dressed in the morning. What if you put on your coat before your jumper? Your jumper would be on top of your coat and that would be silly! When you write an algorithm the order of the instructions is very important.

People use lots of algorithms every day even if they don’t realise it.

Example

We need to make a cake

The algorithm here is a cake recipe. You can find the algorithm to solve this problem in a cookbook!

Now let's play with the algorithms!

Here is a problem:

Translation in English

Someone has a pelican, a panther and an octopus in the bank of a river and he wants to carry them across the river, using a boat. But the boat is small and it can only carry the boatman and a single animal. However, the pelican should not stay with the octopus (the pelican will eat the octopus) and the panther should not stay with the pelican (the panther will eat the pelican). Can you give instructions to the boatman on how to make the transfer?
 

Data:
1 panther
1 pelican
1 octopus
Only one passenger seat in the boat
2 banks of the river

The Greek and the Italian pupils organized a teleconference to play with the algorithms, solving the above problem. Unfortunately, problems with the internet connection didn't allow them to play as they wished!

The students from the Italian school XV Istituto Comprensivo P.Orsi - Syracuse, meet their Greek friends from εκπαιδευτήρια Πάνου - Nafpaktos

And here you can see the solution of the problem by the Greek teams:

As you can see, we used the masks constructed by the children in the previous unit.

3rd place

2nd place

1st place

Remember!

The word algorithm derives from the name of the mathematician, Mohammed ibn-Musa al-Khwarizmi, who was part of the royal court in Baghdad and who lived from about 780 to 850. Al-Khwarizmi's work is the likely source for the word algebra as well.