Bubble sort to char pointers

Question

i am trying to make a program that inserts to an 'char** arr' a char pointer and then sort the char pointers with strcmp but for some reason its just don't work, the code i added is the sorting part of the entire code.

do
    {
        flag = 0;

        for (i = 0; i < num - 1; i++)
        {
            if ((strcmp(arr[i], arr[i + 1])) < 0)
            {
                flag = 1;
                temp = arr[i];
                arr[i] = arr[i + 1];
                arr[i + 1] = temp;
            }

            else if ((strcmp(arr[i], arr[i + 1])) > 0)
            {
                flag = 1;
                temp = arr[i + 1];
                arr[i + 1] = arr[i];
                arr[i] = temp;
            }

            else if ((strcmp(arr[i], arr[i + 1])) == 0)
            {
                flag = 1;
                continue;
            }
        }
    } while (flag == 1);

On an unrelated note, you don't need *three* string comparisons, just one, saving the result to a variable is enough, then compare the variable. — Some programmer dude, Apr 09 '16 at 15:56

score 0 · Answer 1 · answered Apr 09 '16 at 15:56

0

Depends on whether you want ascending order or descending order, you should only swap arr[i] and arr[i+1] in one of the if cases. (either strcmp() < 0 or strcmp() > 0 case)
flag should only be assigned as 1 when swapping actually happens. Otherwise the loop won't stop.

answered Apr 09 '16 at 15:56

timrau

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Thank you, i tried what you said and the program still crashes. what do you think i should do? – Ofek Ezon Apr 09 '16 at 16:55
@OfekEzon Use a debugger to check where it crashed and which pointer has incorrect value. – timrau Apr 09 '16 at 17:09

Bubble sort to char pointers

1 Answers1