Servers

Roger wants to start a cloud computing company. First, he went to some companies to promote his cloud computing system and $N$ of them (numbered $1$ through $N$) showed interest. Each of these $N$ clients has one task, which consists of a number of processes that needs to be executed every second. Let's denote the number of processes for the $i$-th client by $D_i$. Roger, happy to have a bunch