Bullets and Enemies

There are $N$ enemies standing from left to right with strengths $S_1, S_2, \ldots, S_N$. $M$ bullets are to be fired from the left side such that only one bullet is fired at a time. The $i^{th}$ bullet $(1 \le i \le M)$ has power $P_i$ and capacity $C_i$. This means that the $i^{th}$ bullet affects the first $C_i$ **alive** enemies from the left side and decreases the strength of each of those