11. 16 and 8.

Since there are initially 22 candies, in the end, A and B each take 11 candies.

On the one hand, to maximize the number of yellow candies initially, according to B's selection method, B must take two yellow candies each time for the first five selections, and one yellow candy in the last selection. Since B makes a total of six selections, A should select 11 candies in five selections from the four colors. At this point, A's selection method is $11=4+3+2+1+1$.

On the other hand, B must make six selections. To minimize the number of yellow candies initially, A should take one candy of each color in five selections after B's selections, meaning A must take one yellow candy in each of the five selections $(11=4+3+2+1+1)$, and B must take one yellow candy in each of the last three selections. Let $A, B, C, D$ represent the four colors, where $A$ is yellow. The method for A and B to take the minimum number of yellow candies initially is:
$$
\begin{array}{l}
(D D, A B C D) \rightarrow(C C, A B C) \rightarrow(B C, A B) \\
\rightarrow(B B, A) \rightarrow(A B, A) \rightarrow(A,-),
\end{array}
$$

At this point, the number of candies of color $B$ and color $A$ is the same, which does not match the problem statement;
$$
\begin{array}{ll} 
& (D D, A B C D) \rightarrow(C C, A B C) \rightarrow(B C, A B) \\
& \rightarrow(B B, A) \rightarrow(A A, A) \rightarrow(A,-) \\
\text { or } & (D D, A B C D) \rightarrow(C C, A B C) \rightarrow(B B, A B) \\
& \rightarrow(B B, A) \rightarrow(A A, A) \rightarrow(A,-) .
\end{array}
$$

After verification, this matches the problem statement.
11. A and B have a total of 22 candies in four different colors, and

the number of yellow candies is the largest. A and B take turns picking candies according to the following rules until all the candies are taken: B starts, and B takes two candies each time (or the last one), then A takes one candy of each color from the remaining candies. After all the candies are taken, A and B find that they have taken the same number of candies. Find the maximum and minimum values of the number of yellow candies at the beginning.