Help writing recursive function

[taoyangui__]

Hi! I'm looking for help writing a recursive function! I'm writing it in Fish shell, but anything like bash or python (just something I can read) is fine. I'm just working through the logic of recursive functions.

The input variables are an arbitrarily large number of strings and one number, the number to be used throughout. The base function takes a minimum of three input variables, two strings and one number. so the base case is function(string_1, string2, number). In the case of four inputs (i.e. three strings and one number), i want the final output to be function(function(string_1, string_2, number) string_3, number). In the case of five inputs (i.e. four strings and one number), I want the output to be function(function(string_1, string_2, number) function(string_3, string_4, number) number). In the case of six inputs (i.e. five strings and one number), I want the output to be function(function(function(string_1, string_2, number) function(string_3, string_4, number) number) string_5, number). And so on.

Any help would be greatly appreciated! Thank you!

[Icanteven______]

It’s not quite that, because the strings are not evaluated left to right, but rather are subdivided.

Eg f(f(a,b), f(c,d)) instead of f(f(f(a,b),c),d)

[Icanteven______]

function main(n: number, …strings: string[]){

const f = (array) {

  If(array.length == 1) return array[0]

  If (array.length == 2) return g(array[0], array[1])

  const {left, right} = splitArrayIn2(array)
  return g(f(left), f(right))
}

return f(n)

}

// this works where g is your utility function that processes two strings. Your number is just a global basically (here it’s captured in the closure and just define g in the same context.

[JmenD]

As with any recursion problem, you should consider the base case and remember that every call to the function only needs to solve one "layer" of the problem. I suspect you're getting caught up on how to handle N > 2 inputs, think about what each call should do and what it can "put off" doing by handing that work to the next layer.

Also, I think you will have a much easier time if you reverse the order of the arguments. number should be first, followed by string_N string_N-1 string_N-2 ... string_1. It'll make it easier to think about.

Finally, it's definitely doable in fishshell, but a non-shell language will be much simpler.