There are two identical vessels X and Y. is filled with water to the brim and X is empty. There are two pails A and B, such that B can hold half as much water as A. One operation is said to be executed when water is transferred from Y to X using A once and water is transferred to Y from X using B once. If A can hold $$\frac{1}{2}$$ liter of water and it takes 40 operations to equate the water level in X and Y, what is the total volume of water in the system?