The Children and Candies

There are n children with indices $1$ to $n$. The $i$th child has a bag which can hold $Ai$ candies. We have m packets of candies . The $ith$ packet contains $Bi$ candies. Now for each packet we start distributing candies to the children starting from index 1. When the $i$th child bag gets fully filled we continue distributing candies to the $( i+1)$ th child until all the candies from the choose