Logic error with recursion to find smallest in an array

[aijazbaig1]

Huy.
I am using recursion to find the smallest number in a given array. To keep it simple I have fixed the array length at 6.
Heres my code. (I am using Visual C++ version 6)

#include <stdio.h>
#define SIZE 6

int find_smallest(int array[]);

int main()
{
int arr[] = {1,5,3,4,8,6};
int smallest;
smallest = find_smallest(arr);
printf("the smallest number in the array is %d\n",smallest);
return 0;
}

int find_smallest(int array[])
{

static int progress_marker = 0;
register int smallest;


if (progress_marker >= SIZE-2)
{
if (array[SIZE-2] > array[SIZE-1])
smallest = array[SIZE-1];
else smallest = array[SIZE-2];
return smallest;
}
else
{
++progress_marker;
find_smallest(array+progress_marker);
}
}

I doubt if the static variable is playing foul here..nonetheless id appreciate if some gurus would lend me a helping hand albeit virtually..hehe

[madhusudankapoor]

Enjoy...

int find_smallest(int array[])
{

	static int	progress_marker = 0;
	static int	smallest;
	if(0 == progress_marker)
		smallest= array[0];


	if (progress_marker >= SIZE)
		return smallest;
	else
	{
		if(smallest > array[progress_marker] )
			smallest = array[progress_marker];
		progress_marker++;
		find_smallest(array);
	}
}

[RoboTact]

You should pass what you named progress_maker as parameter, otherwise it's not quite recursion. Make prototype as follows:

int find_smallest(int* arr, int length);

This way when you need to move to the tail of array you call

find_smallest(arr+1,length-1);

Though bisection will make stack usage fairer.

[aijazbaig1]

Hi.
I have tried the following recursive version and it works fine (as long as no two elements have the same value )

#include <stdio.h>
#define SIZE 6

void printarray(const int [],const int );
int recur_min(const int *array);

int main()
{
int array[SIZE],i,smallest;
printf("enter the elements of the array and press enter after entering each element\n");
for (i=0;i<=SIZE-1;i++)
scanf("%d",&array[i]);
array[SIZE]='\0';
printarray(array,SIZE);
smallest = recur_min(array);
printf("the smallest in the array is %d\n",smallest);
return 0;
}

void printarray(const int array[], const int size)

{ // Print array on standard output ----------------------------------------
int i;
printf("\n");
for (i=0;i<size; i++)
printf("%d\n",array[i]);
printf("\n");
}

int recur_min(const int *array)

{
static int smallest;
if ( *(array+2) != '\0')
{
smallest = recur_min(array+1);
if (*array < smallest) smallest = *array;
return smallest;
}
else
{
if(*array < *(array+1))
smallest = *array;
else
smallest = *(array+1);
return smallest;
}
}

However it generates a windows error which says it needs to close the non responsive program i.e. the exe file of the project

I am using VC++ version 6.0 as u guys already know. Can somebody explain why? Is it because of stack overflow? but isnt this program a lil too small for that.

Additionally, how do I format my messages so that the code part of the message appears in a neat indented format which is easier to read? Is there something in which I can wrap my code before submitting a message??

I would appreciate any insights from u guys.

Best Regards,
Aijaz Baig.

[RoboTact]

Did you read my comment? It's not quite recursion, so it may be rejected even if you happen to do it right your way.
Try debugging. Run your code step-by-step to figure if it does what you intended. Your code is too complex, there's very simple correct code.

[Calculator]

An integer array should not be 'null terminated' because '\0' == 0. You would probably want to be able to have 0 values in your array. In addition, the use of the static variable is a littlefunny. It would probably cause a stack overflow if there was infinite recursion. You can format your code neatly using the [ code ] [ / code ] tags.