#include <stdio.h>


void rotar( int *a,int *b,int *c,int *d) ;
void rotar2( int *a,int *b,int *c,int *d) ;


int main()
{
    int a,b,c,d;

    a = 10;
    b = 20;
    c = 30;
    d = 40;

    printf( "rotar:  a= %d | b= %d | c= %d | d= %d\n",a,b,c,d );
    rotar( &a,&b,&c,&d );
    printf( "        a= %d | b= %d | c= %d | d= %d\n",a,b,c,d );
    rotar2( &a,&b,&c,&d );
    printf( "rotar2: a= %d | b= %d | c= %d | d= %d\n",a,b,c,d );
return 0;
}


/* forma 1 */
void rotar( int *a,int *b,int *c,int *d) 
/* void rotar( int *d,int *c,int *b,int *a) */
{
    int tmp;
    tmp = *a;
    *a = *d; 
    *d = tmp;
    tmp = *b;
    *b = *c;
    *c = tmp;
    /*
    swap( a, d );
    swap( b, c );
    */
}    

void swap( int *a, int *b)
{
    int tmp;
    tmp= *a;
    *a = *b;
    *b = tmp;    
}    

/* forma 2 */
void rotar2( int *a,int *b,int *c,int *d) 
{
    swap( a, d);
    swap( b, c);
}    

/* forma 3 */
void rotar3( int **a )
{
    


}