```/* nag_double_sort (m01cac) Example Program.
*
* Copyright 2017 Numerical Algorithms Group.
*
* Mark 26.2, 2017.
*/

#include <nag.h>
#include <stdio.h>
#include <nag_stdlib.h>
#include <nag_stddef.h>
#include <nagm01.h>

int main(void)
{
Integer exit_status = 0, i, n;
NagError fail;
double *vec = 0;

INIT_FAIL(fail);

/* Skip heading in data file */
scanf("%*[^\n]");
printf("nag_double_sort (m01cac) Example Program Results\n");
scanf("%" NAG_IFMT "", &n);
if (n >= 1) {
if (!(vec = NAG_ALLOC(n, double)))
{
printf("Allocation failure\n");
exit_status = -1;
goto END;
}
}
else {
printf("Invalid n.\n");
exit_status = 1;
return exit_status;
}
for (i = 0; i < n; ++i)
scanf("%lf", &vec[i]);
/* nag_double_sort (m01cac).
* Quicksort of set of values of data type double
*/
nag_double_sort(vec, (size_t) n, Nag_Ascending, &fail);
if (fail.code != NE_NOERROR) {
printf("Error from nag_double_sort (m01cac).\n%s\n", fail.message);
exit_status = 1;
goto END;
}
printf("Sorted numbers\n\n");
for (i = 0; i < n; ++i)
printf("%10.6g%c", vec[i], (i % 7 == 6 || i == n - 1) ? '\n' : ' ');
END:
NAG_FREE(vec);
return exit_status;
}
```