Assigning Ability Scores

I apologize in advance if this has been asked before but i could not find it...

Im writing a program for a game and the character creation involves rolling 4d6 reroll 1s and dropping the lowest score (in the program its a random number between 6 and 18) and then assigning the ability scores to the stats

example
11 12 18 15 13 12

i havent decided on the stats for my game yet so ill just use the basic DnD abilities
Str - 12
Dex - 13
Con - 15
Int - 12
Wis - 18
Cha - 11

my question is how to have the user choose what ability gets which number by assigning the number to the ability then "checking off the list of numbers" so to speak

anyone who has played a table-top rpg should no where im going with this and if you havent you probly were lost in the beginning

in the program its a random number between 6 and 18

You do realize that's not at all the same, do you?

Put your results in an array, display it in order, present the current stat and let the user type the index of the number to assign to it. Then strike that number and start again. The interface would look something like this:

Code:

Choose your strength
1) 11
2) 12
3) 18
4) 15
5) 13
6) 12
Your choice: -> user types 3
Strength: 18
Choose your dexterity
1) 11
2) 12
3) 15
4) 13
5) 12
Your choice:

And so on.