Puzzle: get exactly 2 liters with the 4 ltr and 7 ltr jars

The Problem:

You've got two jars, one of them fits exactly 7 liters, the other one fits exactly 4 liters. How could you get exactly 2 liters with these two jars? You have unlimited supply of water and you are allowed to spoil some water.


The Solution:

7 0 fill the 7 ltr jar completely
3 4 fill the 4 ltr jar using the 7 ltr one completely
3 0 empty the 4 ltr jar
0 3 fill all water from 7 ltr jar to 4 ltr water
7 3 fill the 7 ltr jar completely
6 4 fill 4 ltr jar from 7 ltr one completely
6 0 empty the 4 ltr jar
2 4 fill 4 ltr jar from 7 ltr one completely
2 0 empty the 4 ltr jar

Now you have exactly 2 ltrs in 7 ltr jar