The above picture develops to the next stage. Without this person, the number of people in each row from left to right is 2, 3, 2, 3, 2, which is exactly 12. Although this person actually existed at that time, there were 13 people, but his hair was gone.

There are 12 people in the picture above, but the first one has a lock of hair on his head.

So what's the problem?

In other words, this tuft of hair is the shorter one in the first column on the right in the next picture. A lock of his hair is dispensable, and his next lock is provided by the black man in the front row.