I am trying to find all possible combinations of a matrix where the values sum to some target. It seems rather straightforward but the solution does elude me at the moment. Here is an example matrix. In this example, I’d like to find all possible matrix positions where the sum is 100. A “position” is taking one value from each column. So, trivially I can get that `((1,1),(5,2),(5,3),(5,4),(5,5))`

and those like it are possible combinations. But finding all of them is escaping me…

Would anyone be willing to help?

```
julia> N = 5
5
julia> L = 5
5
julia> spots = repeat(reverse(collect(range(0,100,length=L))),1,N)
5×5 Array{Float64,2}:
100.0 100.0 100.0 100.0 100.0
75.0 75.0 75.0 75.0 75.0
50.0 50.0 50.0 50.0 50.0
25.0 25.0 25.0 25.0 25.0
0.0 0.0 0.0 0.0 0.0
```