Chef Bakes Cake 3

Chef is an expert baker. Each cake costs him $30$ coins to make, and then he sells each for $50$ coins. Chef is going to sell cakes for $N$ days, numbered $1, 2, \ldots, N$. On the $i$-th day, $A_i$ customers will visit Chef's shop and buy exactly $1$ cake each (if Chef has any cakes available, that is). However, Chef preferring uniformity, will always produce the same number of cakes at the sta