I am currently trying to sort an array of pointers using selection sort, but with no success. I need to sort an array of int values with only pointers. I have already stored values in the array, and only thing left to do is to sort these values.
Here is my code:
void fill_rand_ver2(int *pointer, int size)
{
int randNbr;
int *i;
for(i = pointer; i < (pointer + size); i++)
{
randNbr = (rand()%10)+1;
*i = randNbr;
}
}
// sort array with help of selection sort using pointer
void sort_ver2(int *pointer, int size)
{
int *i, *j, swap;
for(i = pointer; i < (pointer + size); i++)
{
for(j = i + 1; j < (pointer + size); j++)
{
if(*j < *i)
{
swap = *i;
*i = *j;
*j = swap;
}
}
}
}
// print out both arrays using pointer
void print_values_ver2(char *string, int *pointer, int size)
{
int *i;
printf("%s", string);
printf("\n");
for(i = pointer; i < (pointer + size); i++)
{
printf("%d,", *i);
}
printf("\n\n");
}
When I run the program and print data, the entered values are not sorted and remain at the same place. I would appreciate any help given.
I believe you want to sort by value, not by address, so it should be:
void sort_ver2(int *pointer, int size)
{
int *i, *j, swap;
int *end = NULL;
if(size < 2 || pointer == NULL)
return;
end = pointer + size - 1;
for(i = pointer; i < end; i++)
{
for(j = i + 1; j <= end; j++)
{
if(*j < *i)
{
swap = *i;
*i = *j;
*j = swap;
}
}
}
}
Even if you would like to sort by address, your if statement is incorrect, as j is always greater than i in your code.
EDIT: added end variable to address issue with incorrect range of the inner for loop. Credits to @WhozCraig.