How to Sort a 2D array?

Question

I need help with sorting 2D array. I\'ve got array with two rows

[5, 3, 4, 1, 2]
[10,20,30,40,50]

and I need to sort it to look like this:

Answer 1

transpose the 2D array java multi-dimensional array transposing

use Arrays.sort(T[] a, Comparator c) where the comparator compares on index 0 of each row

transpose the result again:

e.g.

from: [5,3,4,1,2] [10,20,30,40,50]

obtain [5, 10] [3, 20] [4, 30] [1, 40] [2, 50]

then sort them to [1, 40] [2, 50] [3, 20] [4, 30] [5, 10]

then transpose again to: [1,2,3,4,5] [40,50,20,30,10]

or implement quicksort by yourself.