Sorting array or AssocArrays by value.

[Derek Parnell]

On Sun, 4 May 2008 13:11:23 +0000 (UTC), Me Here wrote:

> I need them ordered by the /values/ not the keys.
> 
> Eg. Given, (whether array or hash):
> 
> //index/key  0  1  2  3  4  5  6  7 8 
> uint a[] =    [ 3, 1,  8, 6, 4, 9, 2, 5, 7 ];
> 
> I need to output:
> // value  - index
> 1 - 1
> 2 - 6
> 3 = 0
> 4 - 4
> 5 - 7
> 6 - 3
> 7 - 8
> 8 - 2
> 9 - 5

The trick I use for this is to have two AAs. When the set is small,
performance isn't really an issue.


import std.stdio;
void main()
{
   int[int] theArray;
   theArray[0] = 3;
   theArray[1] = 1;
   theArray[2] = 8;
   theArray[3] = 6;
   theArray[4] = 4;
   theArray[5] = 9;
   theArray[6] = 2;
   theArray[7] = 5;
   theArray[8] = 7;

   int[int] altArray;
   foreach(int i; theArray.keys)
   {
       altArray[ theArray[i] ] = i;
   }
   
   foreach(int i; altArray.keys.sort)
       writefln("%s - %s", i, altArray[i]);
       

}

-- 
Derek Parnell
Melbourne, Australia
skype: derek.j.parnell