Compare same words

Question

I'm new in programming in C and I got 2 problems. I have two string, then I need to split them into words and find out if both strings contains same words. I will explain it with my code.

Input:

"He said he would do it."
"IT said: 'He would do it.'"

This two string are placed into two arrays. At first I need to parse words from others characters.

Call function:

char ** w1 = parse(s1, &len1);

Variable len counts number of rows (words).

Function parse:

char ** parse(char *w, int * i)
{
   int j = 0, y, dupl = 0; //variables for cycles and duplicate flag
   char d[] = " <>[]{}()/\"\\+-*=:;~!@#$%^&_`'?,.|";
   char* token = strtok(w, d);
   unsigned len = strlen(token), x;
   unsigned plen = len;
   char ** f = (char**) malloc(len * sizeof (char*));
   while (token != NULL)
   {
       len = strlen(token);
       for (x = 0; x < len; x++)
       {
           token[x] = tolower(token[x]);
       }

       for (y = 0; y < *i; y++) //cycle for deleting duplicated words
       {
           if (equals(token, f[y]) == 1)
           {
               dupl = 1; break;
           }

       }
       if (dupl == 1)
       {
           token = strtok(NULL, d);
           dupl = 0;
           continue;
       }

       if (len >= plen)
       {
           f = (char**) realloc(f, (len+1) * sizeof (char*));
           plen = len;
       }
       else
           f = (char**) realloc(f, (plen+1) * sizeof (char*));

       f[j] = token;
       token = strtok(NULL, d);
      *i = *i + 1;
       j++;
   }
   free(token);
   return f;
}

Ok, now i have 2x 2Darrays, then just sort it (qsort(w1, len1, sizeof (char*), cmp);) and compare it:

for (i = 0; i < len2; i++)
    if (equals(w1[i], w2[i]) == 0)
        return 0;

Function equals:

int equals(char *w1, char *w2)
{
   if (strcmp(w1, w2) == 0)
       return 1;
   return 0;
}

I know that all of this can be faster, but at first I need to solve my problem. This works for input which I wrote at the beginning, but when I type something long e.g.500 characters, my result is Aborted. I think that the problem is here:

f = (char**) realloc(f, (len+1) * sizeof (char*));

but dunno why. Second thing is, that I can't free my arrays. This

void Clear (char ** w, int max)
{
   int i;
   for (i = 0; i < max; i++)
       free(w[i]);
   free(w);
}

gives me a segmentation fault. Thanks for your time and I'm sorry for my bad english and bad programming skills.

score 0 · Answer 1 · answered Dec 06 '13 at 13:15

0

It seems to have confused the word length and number of words in the parse function in your logic.

char ** f = (char**) malloc(len * sizeof (char*));

I think for example of len in portions of the above are as should be the number of words rather than characters.

answered Dec 06 '13 at 13:15

BLUEPIXY

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I meant this `len` as number of characters. I have to get number of column cause of the longest word in 2d array. – Grim Dec 06 '13 at 13:47
@user3013004 if in the case of allocating the memory as a string then it should be `sizeof(char)` rather than `sizeof(char *)`. Besides, it looks like it is not used. Further it appears `free(token)` As to free area is not secured. – BLUEPIXY Dec 06 '13 at 14:18
@user3013004 I think it is as not 2Darray If you were allocate memory as the maximum length of the string. – BLUEPIXY Dec 06 '13 at 14:30
@user3013004 also, It seems that it's "a segmentation fault" in the function `Clear` is because does not secure the double. – BLUEPIXY Dec 06 '13 at 14:43

Compare same words

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