Linear Search in C

tsj · 15 Mar 2007 at 10:20

I'm having some problems with a linear search in C
The values of the strings in arrdetails.team array are:

MAX_TEAMS is equal to 12

arrdetails[0].team = manu
arrdetails[1].team = liverpool
arrdetails[2].team = 0
arrdetails[3].team = 0
arrdetails[4].team = 0
arrdetails[5].team = 0
arrdetails[6].team = 0
arrdetails[7].team = 0
arrdetails[8].team = 0
arrdetails[9].team = 0
arrdetails[10].team = 0
arrdetails[11].team = 0

I am looking for the FIRST position of 0, in the case above it should be 2.

Code:

int linear_search() {

printf("\n **LINEAR SEARCH** \n");
        //find next team pos
        int i;
        char target[1];
        target[1] = "0";
        int tm_comp;

        for (i = 0; i < MAX_TEAMS; i++) {
printf("\nfound pos is called %s",arrdetails[i].team);
                tm_comp = (strcmp(arrdetails[i].team, target));
              if (tm_comp == 0) {
printf("\nfound pos is %d \n",i);
                return i;
                }
        }
        printf("\nfound pos is %d \n",i);
}

Please help me get this working

Thanks

happytechie · 15 Mar 2007 at 10:32

what is it doing now?

Paul

tsj · 15 Mar 2007 at 10:33

Oh it keeps returning position 12.

happytechie · 15 Mar 2007 at 11:00

have you got your main method and header files to save me writing one

SKILL · 15 Mar 2007 at 17:48

Just had a play and the problem is due to the "target" variable/string,

If you replace:

char target[1];
target[1] = "0";

Those two lines with the following:

char *target = "0";

It should work properly, can't remember if that will allocate the memory properly as it's been too long since I last coded properly, but it should do and seems to work fine on my pc...

tsj · 15 Mar 2007 at 20:31

SKILL said:
Just had a play and the problem is due to the "target" variable/string,

If you replace:

char target[1];
target[1] = "0";

Those two lines with the following:

char *target = "0";

It should work properly, can't remember if that will allocate the memory properly as it's been too long since I last coded properly, but it should do and seems to work fine on my pc...

Sorry for late reply... I just tried that and it worked a treat. Thanks for that

Just gotta get this finished by next week now.

SKILL · 15 Mar 2007 at 21:20

No worries, one thing though, always look at the compiler warnings, your code immediately gave a warning ('pointer to integer without a cast' iirc), which let me know what line it was and also an idea of what the problem was

Although the idea part only comes after seeing that warning hundreds of times

tsj · 16 Mar 2007 at 00:46

SKILL said:
No worries, one thing though, always look at the compiler warnings, your code immediately gave a warning ('pointer to integer without a cast' iirc), which let me know what line it was and also an idea of what the problem was

Although the idea part only comes after seeing that warning hundreds of times

nice one. thanks for advice m8

Visage · 16 Mar 2007 at 09:17

That line should be:

const char * const target = "0";

To avoid risks of memory corruption.