Imagine we have two empty stacks of integers, S1 and S2. Draw a picture of each stack after the following operations:

pushStack(S1, 2); //push 2 into S1

pushStack(S1, 4);

pushStack(S1, 6);

pushStack(S1, 8);

pushStack(S1, 10);

pushStack(S1, 12);

while ( !emptyStack(S1) )

{

popStack(S1, x); //pop the top item of S1 and save it to variable x

popStack(S1, x);

pushStack(S2, x)

}