Hello All,
In the prefix sums challenge problem, it is mentioned:
Instead of adding, we multiply, and instead of subtracting, we divide
Am I correct to assume the following?

Instead of adding, we multiply means that while calculating the Prefix Products array
prefix[k] = prefix[k  1] * arr[k]

instead of subtracting, we divide means that the range product of subarray in indices
[L,R]
inclusive, will beprefix[R]/prefix[L  1]
Also, does we calculate the answer modulo a given M
mean that we will not use prefix[R]/prefix[L  1]
to find the range product of subarray, but will instead use something like <some numerator> mod M
?
Actually I’m not able to get the correct answer, perhaps because I have not understood the question correctly. Could you please also let me know if I need any prerequisites for this question other than the Prefix Sums resource itself? I have basic knowledge of Modular (Modular Arithmetic · USACO Guide), but I’m not very aware about its properties.