Thread: My call by reference bubble sort code isn't displaying the correct output

The program compiles, however the output is incorrect

Output:

Code:

Input size of array5
Input elements3
5
4
7
8
Enter 1 to sort in ascending order,
Enter 2 to sort in descending order: 1

Data items in ascending order
   0327673276716064169201606420320
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[Process completed]

Code:

/* This program puts values into an array, sorts the values into
 ascending order, and prints the resulting array. */
#include <stdio.h>

void sortascending( int * const array, const int size ); /* prototype */
void sortdescending( int * const array, const int size );
void swap( int *element1Ptr, int *element2Ptr ); /* prototype */

int main( void )
{
	
	int i; /* counter */
	int order;
	/* initialize array a */
	int SIZE;
	int a[ SIZE ];
	printf("Input size of array");
	scanf("%d", &SIZE);
	printf("Input elements");
	for (i=0; i<SIZE; i++) {
		scanf("%d", &a[SIZE]);
	}
	
	printf( "Enter 1 to sort in ascending order,\n" 
           "Enter 2 to sort in descending order: " );
	scanf( "%d",  &order );
	
	/* sort array in ascending order; pass function ascending as an
     argument to specify ascending sorting order */
	switch (order) {
		case 1:
			sortascending( a, SIZE);
			printf( "\nData items in ascending order\n" );
			/* loop through array a */
			for ( i = 0; i < SIZE; i++ ) {
				printf( "%4d", a[ i ] );   
			} /* end for */
			printf( "\n" );
			break;
		case 2:
			sortdescending( a, SIZE);
			printf( "\nData items in descending order\n" );
			/* loop through array a */
			for ( i = 0; i < SIZE; i++ ) {
				printf( "%4d", a[ i ] );   
			} /* end for */
			printf( "\n" );
			break;
		default:
			break;
			return 0; /* indicates successful termination */
	} /* end main */
}

/* sort an array of integers using bubble sort algorithm */
void sortascending( int * const array, const int size )
{
	int pass; /* pass counter */
	int j;    /* comparison counter */
	
	/* loop to control passes */
	for ( pass = 0; pass < size - 1; pass++ ) {
		
		/* loop to control comparisons during each pass */
		for ( j = 0; j < size - 1; j++ ) {
			
			/* swap adjacent elements if they are out of order */
			if ( array[ j ] > array[ j + 1 ] ) {
				swap( &array[ j ], &array[ j + 1 ] );
			} /* end if */
			
		} /* end inner for */
		
	} /* end outer for */
	
} /* end function bubbleSort */

/* sort an array of integers using bubble sort algorithm */
void sortdescending( int * const array, const int size )
{
	int pass; /* pass counter */
	int j;    /* comparison counter */
	
	/* loop to control passes */
	for ( pass = 0; pass < size - 1; pass++ ) {
		
		/* loop to control comparisons during each pass */
		for ( j = 0; j < size - 1; j++ ) {
			
			/* swap adjacent elements if they are out of order */
			if ( array[ j ] < array[ j + 1 ] ) {
				swap( &array[ j ], &array[ j + 1 ] );
			} /* end if */
			
		} 			
	} 
	
}
/* swap values at memory locations to which element1Ptr and
 element2Ptr point */
void swap( int *element1Ptr, int *element2Ptr )
{
	int hold = *element1Ptr;
	*element1Ptr = *element2Ptr;
	*element2Ptr = hold;
} /* end function swap */

You're not reading the items into valid positions within the array, to begin with.
Look at your scanf.

If you declare an array as

Code:

int array[SIZE]

The the value of SIZE needs to be known at compile time.

If you want to read SIZE in from the use during program execution, you have to allocate the array dynamically:

Code:

..read in value for SIZE
int *array;
if ((array=malloc(SIZE*sizeof(int)))==NULL)
{
    printf("Array allocation failed\n");
    abort();
}