Chef and Street Food

in Chefland, there is a very famous street where $N$ types of street food (numbered $1$ through $N$) are offered. For each valid $i$, there are $S_i$ stores that offer food of the $i$-th type, the price of one piece of food of this type is $V_i$ (the same in each of these stores) and each day, $P_i$ people come to buy it; each of these people wants to buy one piece of food of the $i$-th type. C