Extended Viewing

After many years of work, Chef has managed to open an art gallery showcasing all his pieces. There are $N$ pieces of art, arranged in a line from left to right. The $i$-th piece from the left has a *beauty* of $A_i$. Each $A_i$ equals either $1$ or $2$. A famous art critic is visiting the gallery, and Chef knows that he will move through the gallery as follows. Initially, the critic will