Help with Duff's Device in C++

failbot (1)
Hi, I am working on this code:

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#include <iostream>
using namespace std;
 
send(to, from, count)
{
         register int *to, *from;
         register int count;
         {
                 register n=(count+7)/8;
                 switch(count%8){
                 case 0: do{     *to++ = *from++;
                 case 7:         *to++ = *from++;
                 case 6:         *to++ = *from++;
                 case 5:         *to++ = *from++;
                 case 4:         *to++ = *from++;
                 case 3:         *to++ = *from++;
                 case 2:         *to++ = *from++;
                 case 1:         *to++ = *from++;
                         }while(--n>0);
                 }
         }
}
 
int main()
{
	int i;
	int a[5]={1,2,3,4,5};
	int b[]={0,0,0,0,0};
 
	/*output each a[i] and b[i] in decimal separated by a Tab on one line*/
	for(i=0; i<5; i++)
		printf("%d\t%d\n", a[i], b[i]);
 
	printf("----------------\n");
 
	send(b, a, 5);
 
	for(i=0; i<5; i++)
		printf("%d\t%d\n", a[i], b[i]);
}

and am getting the following error:

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expected constructor, destructor, or type conversion before '(' token
I've tried using different types but it only gives me more errors. Can anyone help me fix this?
savavampir (146)
WTF? Is this a joke?
Last edited on
bluecoder (763)
What are you trying to do by using the pointer to increament ?
anonymous23323124 (1383)
send(to, from, count)

Is this a function header? It should have a return type (void if nothing is to be returned).

EDIT: Furthermore, the parameters should have types, as well (int, char, bool, etc).
Last edited on
coder777 (8450)
It's not a joke: http://en.wikipedia.org/wiki/Duff%27s_device

Todays C just looks different (if that makes sense nowadays is another question)

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send(register int *to, register int *from, register int count)
{
                 register int n=(count+7)/8;
                 switch(count%8){
                 case 0: do{     *to++ = *from++;
                 case 7:         *to++ = *from++;
                 case 6:         *to++ = *from++;
                 case 5:         *to++ = *from++;
                 case 4:         *to++ = *from++;
                 case 3:         *to++ = *from++;
                 case 2:         *to++ = *from++;
                 case 1:         *to++ = *from++;
                         }while(--n>0);
                 }
         }
}
savavampir (146)
Thanks for clarification. Never heard of it before.
Last edited on
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