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

/*
int sum( int * arr, int N )
{
    int i;
    int theSum = 0;

    for( i = 0; i < N; i++ )
        theSum += arr[ i ];

    return theSum;
}
*/

int sum( int *arr, int N )
{
    int *p = arr;
    int *endMarker = arr + N;
    int theSum = 0;

    while( p != endMarker )
        theSum += *p++;

    return theSum;
}
/*
 * Fill in *N with # items read
 * Return arr of items allocated from memory heap
 */
int * readNumbers( int *N  )
{
    int capacity = 5;
    int itemsRead = 0;
    int *arr = malloc( capacity * sizeof( int ) );
    int x;

    printf( "Enter as many numbers, followed by ***\n" );
    while( scanf( "%d", & x ) == 1 )
    {
        if( itemsRead == capacity )
        {
            capacity *= 2;
            arr = realloc( arr, capacity * sizeof( int ) );
            if( arr == NULL )
                return NULL;
        }
        arr[ itemsRead++ ] = x;
    }

    *N = itemsRead;
    return arr;
}

#define MAX_STRING 1023


/*
 * Fill in *N with # items read
 * Return arr of items allocated from memory heap
 */
char * * readStrings( int *N  )
{
    char buffer[ MAX_STRING + 1 ];
    int capacity = 3;
    int itemsRead = 0;
    char * *arr = malloc( capacity * sizeof( char * ) );
    int x;

    printf( "Enter as many strings, followed by ***\n" );
    while( scanf( "%1023s", buffer ) == 1 )
    {
        if( strcmp( buffer, "***" ) == 0 )
            break;

        if( itemsRead == capacity )
        {
            capacity *= 2;
            arr = realloc( arr, capacity * sizeof( char * ) );
            if( arr == NULL )
                return NULL;
        }
        arr[ itemsRead++ ] = strdup( buffer );
    }

    *N = itemsRead;
    return arr;
}

/*
 * Testing array expansion
 */
int main( )
{
    char * * arr;
    int theSum;
    int i;
    int N;

    arr = readStrings( &N );

    for( i = 0; i < N; i++ )
        printf( "String #%d: %s\n", i, arr[ i ] );


    /* Cleanup mess */
    for( i = 0; i < N; i++ )
        free( arr[ i ] );
    free( arr );

    return 0;
}