c# - Writing list to CSV file -

i have list of list of int called nn write csv file this:

list<list<int>> nn = new list<list<int>>(); 

the nn list:

1,2,3,4,5,6 2,5,6,3,1,0 0,9,2,6,7,8 

and output csv file should this:

1,2,0 2,5,9 3,6,2 4,3,6 5,1,7 6,0,8 

what best way achieve that?

if there better representation recommend instead of nested list i'll glad know.

(the purpose each list of int weights between last , next layer in neural network).

here how can it:

list<list<int>> nn = new list <list<int>> {     new list<int> {1,2,3,4,5,6},     new list<int> {2,5,6,3,1,0},     new list<int> {0,9,2,6,7,8} };  //get expected number of rows var numberofrows = nn[0].count;   var rows =     enumerable.range(0, numberofrows) //for each row     .select(row => nn.select(list => list[row]).tolist()) //get row data columns     .tolist();  stringbuilder sb = new stringbuilder();  foreach (var row in rows) {     sb.appendline(string.join(",", row)); }  var result = sb.tostring();