C code for A recursive implementation of the quicksort algorithm.

void quicksort(int x[], int l, int u)

{

int * j; int k;

if (l > =u)

return;

else

{

partition (x, l,u,&j);

quicksort (x, l, j -1);

quicksort (x, j+1, u);

return;

}

}

void partition (int x [], int l, int u,int *j)

{

int k, m,n, i, temp, int * j;

k = x [l]; /* k is the element whose final */

n = u; /* position is required */

m =l;

while (m <>

{

while (x[m] <= k && m <>

m++ ; /* move the lower index up */

while (x[n] > k)

n --; /* reduce the upper index */

if (m

{

/*interchange x[m] & x[n] */

temp=x[m];

x[m]=x[n];

x[n]=temp;

} /* end if */

} * end while */

x[l]= x[n];

x[n]=k;

* j = n;

return;

}