#include <stdio.h> #include <conio.h> int split ( int*, int, int ) ; void main( ) { int arr[10] = { 11, 2, 9, 13, 57, 25, 17, 1, 90, 3 } ; int i ; void quicksort ( int *, int, int ) ; clrscr( ) ; printf ( "Quick sort.\n" ) ; printf ( "\nArray before sorting:\n") ; for ( i = 0 ; i <= 9 ; i++ ) printf ( "%d\t", arr[i] ) ; quicksort ( arr, 0, 9 ) ; printf ( "\nArray after sorting:\n") ; for ( i = 0 ; i <= 9 ; i++ ) printf ( "%d\t", arr[i] ) ; getch( ) ; } void quicksort ( int a[ ], int lower, int upper ) { int i ; if ( upper > lower ) { i = split ( a, lower, upper ) ; quicksort ( a, lower, i - 1 ) ; qu...