Frederick Ding wrote:
Hi, guys!
I have two questions of some kind of style problem:
1. Is there a better one that can substitute this:
Yes, see below.
while (1) {
for (i = 0; i < 6; i++) {
scanf("%d", &a[i]);
}
if ((a[0] == 0) && (a[1] == 0) && (a[2] == 0) && (a[3] == 0) &&
(a[4] == 0) && (a[5] == 0))
break;
else {
/* do other things */
}
}
I doubt that the while(1) is decent or not?
Can I find a better one than the "forever" loop?
2. still in the code above:
if (i == 0) break;
else {
}
or
if (i == 0) break;
...... /* do other things without else */
which one is better?
Here's another way to write the code above. First of all we create a
couple of functions, one that reads numbers and one that tests the array
for emptiness. As you see, these are general functions operating on
arrays of any size. The functions can be optimized later and you can
even add error handling and asserts...
int read_numbers(FILE* f, int dest[], size_t nelem)
{
size_t i;
for(i = 0; i < nelem; i++)
fscanf(f, "%d", &dest[i]);
return 1;
}
int empty_array(int arr[], size_t nelem)
{
size_t i;
for(i = 0; i < nelem; i++)
if(arr[i] != 0)
return 0;
return 1;
}
Back to your loop. No more breaks, only one magic number and no
while(1). So much nicer, isn't it?
....
int myarray[6];
size_t nelem = sizeof myarray / sizeof *myarray;
while(read_numbers(stdin, myarray, nelem)
&& !array_empty(myarray, nelem)) {
/* Do stuff */
}
....
Boa
