Sorting a multidimensional array

[grima]

Hi all,

I would like to sort two arrays (two vectors) after the first and then after the second array in ascending order.

Is there a quick way?

Thanks,
grima

[AleaIactaEst]

Can you explain what you're trying to achieve more in detail ?

[grima]

Hi AleaIactaEst,

yes I can ;)

I have to arrays:

a[0] = 3;   b[0] = 4;
a[1] = 4;   b[1] = 2;
a[2] = 4;   b[2] = 0;
a[3] = 1;   b[3] = 5;
a[4] = 3;   b[4] = 2;

and my goal is to sort the arrays this way:

a[0] = 1;   b[0] = 5;
a[1] = 3;   b[1] = 2;
a[2] = 3;   b[2] = 4;
a[3] = 4;   b[3] = 0;
a[4] = 4;   b[4] = 2;

Thanks and best wishes,
grima

[AleaIactaEst]

The best way to achieve this is to use a struct like this:

struct data {
	int a;
	int b;
};

data ab[5];

At first sort the array ab with any sorting algorithm with respect to the value of b. After that you just need to sort the array again using a stable sorting algorithm for the a component.

For more detailed information about stable sorting algorithms see Wikipedia (http://en.wikipedia.org/wiki/Sorting_algorithm#Stability) or do a search for stable sorting algorithms.