C Tutorial - Advanced Pointers

/* ex3 Sorting ints with qsort */
//

#include <stdio.h>
#include <stdlib.h>

int comp(const int * a,const int * b)
{
  if (*a==*b)
    return 0;
  else
    if (*a < *b)
        return -1;
     else
      return 1;
}

int main(int argc, char* argv[])
{
   int numbers[10]={1892,45,200,-98,4087,5,-12345,1087,88,-100000};
   int i;

  /* Sort the array */
  qsort(numbers,10,sizeof(int),comp) ;
  for (i=0;i<9;i++)
    printf("Number = %d\n",numbers[ i ]) ;
  return 0;
}

Number = -100000
Number = -12345
Number = -98
Number = 5
Number = 45
Number = 88
Number = 200
Number = 1087
Number = 1892

That completes this lesson on advanced use of pointers. In the next lesson, I'll look at some other advanced data structures.

• Storing Data in RAM
• About Example 1- The Linked List Implementation
• Explanation of Example 1 Continued
• More about Example 1
• Learn About Function Pointers
• An Example with Function Pointers
• Other Uses of a Function Pointer
• Example 3 - Using qsort to sort Ints