Get the top nth values from a rectangular array

Question

I am reading a txt file for strings that represent integers. The file is space delimited. I have created an array[10,2]. Everytime the strings 1~10 is found in the file I increment array[n,0] by 1. I also feed array[n,1] with numbers 1~10.

i.e. txt file contents:

1/1/1 10/1/2001 1 1 10 2 2 3 1 5 10 word word 3 3 etc..

• streamreader reads 1/1/1 and determines that is is not 1~10
• streamreader reads 10/1/2001 and determines that it is not 1~10
• streamreader reads 1 and ++array[0,0]
• streamreader reads 1 and ++array[0,0]
• streamreader reads 10 and ++array[9,0]
• etc..

The result will be:

• '1' was found 3 times
• '2' was found 2 times
• '3' was found 3 times
• '5' was found 1 time
• '10' was found 2 times

My problem is that I need this array placed in order(sorted) by value of column 0 so that it would be:

1
3
2
10
5

The 2nd column in the array is so I can tell what the original(string that was found the most) was. example: array[0,0]= 5//number of times '1' is found in the txt file array[0,1]=1//this is so i know after the sort that array[0,0] value was for '1' array[1,0]= 10//number of times '2' is found in the txt file array[1,1]= 2//this is so i know after the sort that array[1,0] value was for '2'

before I only had a single deminsional array. When I sorted the array I had no way of knowing what the original value of array[0] was so I decided to make a rec array so that array[0,1] switches from 1 to 2 so i could know which string actually shows up the most. does this make more since?

Answer 1

As a suggestion, perhaps you might consider using a dictionary of int to int. That way you could support n digit values (rather than a fixed range). Though I'm not sure I understand what else the second dimension of the array is storing?

To output them in order using your current solution, assuming your multi-array called _countsIndexedByValues;

var orderedCounts = _countsIndexedByValues.Select((innerArr, i) => new { Count = innerArr[0], Value = i}).OrderBy(u => u.Count);
orderCounts.ToList().ForEach(u => Console.Out.WriteLine(String.Format("'{0}' was found {1} times", u.Value, u.Count);

This is making use of both LINQ and anonymous types... Where I used an anonymous type you could use a Pair or whatever else you want.