Last Time with this Program ... I swear!

Anyone?

Quote:

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Originally Posted by DonFord81

Anyone?

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be patient

1. to zero arrays at the beginning enough to write

Code:

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        char matrix_array[DIM][BITNSLOTS(DIM)] ={0};
        char U_array[BITNSLOTS(UPPER)] ={0};
        int combination[LOWER]={0};

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No need to call memset

2.

Code:

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#define BITMASK(b) (1 << ((b) % CHAR_BIT))

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What bit do you want to set when b == 1?

3. test_all_zero instead of doing what its name suggests - checks only the

Code:

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if (BITTEST(bitarray, 0))
                {
                        return 0;
                }
                else
                {
                        return 1;
                }

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I could not compile and debug your program because some function is missing.

Do you pay attention to the compiler warnings?

The function that's probably missing for you is <combination.h>, which is not standard in the C library. I can include the code snippet I used for it, since I found it on an internet forum for such things.

I changed the test_all_zero code per your suggestion.

Code:

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int test_all_zero(char* bitarray, int n){
    int i;
    int counter = 0;
    for (i=0; i<n; i++){
        if (!BITTEST(bitarray, i)){
          counter++;
          }
        }
    if (counter == n){
      return (1);
      }
    else{
        return (0);
        }
}

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And here's the <combination.h> header file:

Code:

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/*
        next_comb(int comb[], int k, int n)
                Generates the next combination of n elements as k after comb

        comb => the previous combination ( use (0, 1, 2, ..., k) for first)
        k => the size of the subsets to generate
        n => the size of the original set

        Returns: 1 if a valid combination was found
                0, otherwise
*/
int next_comb(int comb[], int k, int n) {
        int i = k - 1;
        ++comb[i];
        while ((i >= 0) && (comb[i] >= n - k + 1 + i)) {
                --i;
                ++comb[i];
        }

        if (comb[0] > n - k) /* Combination (n-k, n-k+1, ..., n) reached */
                return 0; /* No more combinations can be generated */

        /* comb now looks like (..., x, n, n, n, ..., n).
        Turn it into (..., x, x + 1, x + 2, ...) */
        for (i = i + 1; i < k; ++i)
                comb[i] = comb[i - 1] + 1;

        return 1;
}

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However, for DIM = 5 and LOWER = 3, I'm still getting an incorrect answer.

I can't figure out if my for/while loops are even engaging, since it seems that my program block is just getting skipped. Is that what's happening?

I still don't know what the program is doing wrong. I thought it might be something along the lines of having forgotten to run "make_matrix" after every instance of changing U_array, but I've checked the code, and I do run "make_matrix" after every change in U_array, so that's not the problem.

Can anyone please help me?