Question

i will take either python of c# solution

i have about 200 numbers:

 19.16 
 98.48 
 20.65 
 122.08 
 26.16 
 125.83 
 473.33 
 125.92 
 3,981.21 
 16.81 
 100.00 
 43.58 
 54.19 
 19.83 
 3,850.97 
 20.83 
 20.83 
 86.81 
 37.71 
 36.33 
 6,619.42 
 264.53 
...
...

i know that in this set of numbers, there is a combination of numbers that will add up to a certain number let’s say it is 2341.42

how do i find out which combination of numbers will add up to that?

i am helping someone in accounting track down the correct numbers

Answer 1

[Begin Edit]:

I misread the original question. I thought that it said that there is some combination of 4 numbers in the list of 200+ numbers that add up to some other number. That is not what was asked, so my answer does not really help much.

[End Edit]

This is pretty clunky, but it should work if all you need is to find the 4 numbers that add up to a certain value (it could find more than 4 tuples):

Just get your 200 numbers into an array (or list or some IEnumerable structure) and then you can use the code that I posted. If you have the numbers on paper, you will have to enter them into the array manually as below. If you have them in softcopy, you can cut and paste them and then add the numbers[x] = xxx code around them. Or, you could cut and paste them into a file and then read the file from disk into an array.

  double [] numbers = new numbers[200];
  numbers[0] = 123;
  numbers[1] = 456; 

  //
  // and so on.
  //

  var n0 = numbers;
  var n1 = numbers.Skip(1);
  var n2 = numbers.Skip(2);
  var n3 = numbers.Skip(3);

  var x = from a in n0
          from b in n1
          from c in n2
          from d in n3
          where a + b + c + d == 2341.42
          select new { a1 = a, b1 = b, c1 = c, d1 = d };

  foreach (var aa in x)
  {
    Console.WriteLine("{0}, {1}, {2}, {3}", aa.a1, aa.b1, aa.c1, aa.d1 );
  }