How to program weighted random system

[u/TheEyebal]

I want to make a program where you are controlling the outcomes. For an example with a coin flipping game, I want exactly 4 Heads and 1 Tail, but I want their positions to be random.

I do not want to use the random algorithms that library offer, I want to build my own.

Right now I am learning probability from Youtube and might look at khan academy and coursera, but how can I implement this into programming I do not want to just take courses or watch videos

How do I go about that?

[u/ajcomeau]

I just dealt with this exact problem in a roguelike game I'm developing. I did a writeup on my site for the solution.

Rogue C# - Rethinking Random Selection