So I need to scan in a dictionary of words, max length 19 and dynamically allocate memory to set the size of the dictionary array. I am stuck on how to do this.
fscanf(ifp, "%d", &numwords); //Number of words in dictionary
char ** dictionary;
for(i = 0; i < numwords; i++){
for(j = 0; j < 20; j++){
dictionary[i][j] = (char *) malloc(20 * sizeof(char));
fscanf(ifp, "%s", &dictionary[i][j]);
//printf("%s\n", dictionary[i]); //tests that the letter is read in correctly
}
}
I am lost on what is wrong. Any help would be greatly appreciated.
You need to allocate memory to hold the list of char*
:
dictionary = malloc(sizeof(char*) * numwords);
and when you are allocating the char
array:
dictionary[i] = malloc(20); /* No [j] */
Note that sizeof(char)
is guaranteed to be 1
so it can be omitted from the malloc()
argument. When reading the strings, prevent buffer overrun by specifying the maximum width allowed:
fscanf(ifp, "%19s", dictionary[i]);
There is no requirement for the inner loop. The program needs to read numwords
from the file, only the outer for
is required.
Check return values from functions ( malloc()
does not return NULL
for example and fscanf()
returns the number of expected assignments).
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