How do I count the number of words with the same length in a array of strings C-CodePudding

I'm opening and reading a dictionary file and counting how many words are in the file. Then I'm storing each word individually in an array of strings. After that, I sorted the words by length and in alphabetical order, using the funtion qsort(). Right now, I'm trying to access the table and count how many words have the same length, but I'm have some difficulties to decide on how I should proceed next. The code I have written so far is this:

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#define MAX_STR 100

/* Sorting the words by length and alphabtichal order,
being legnth priority number one */

int compare(const void *a, const void *b){

    const char **str_a = (const char **)a;
    const char **str_b = (const char **)b;

    int len1 = strlen(*str_a);
    int len2 = strlen(*str_b);
    if (len1 < len2) return -1;
    if (len1 > len2) return  1;

    return strcmp(*str_a, *str_b);
}

int main (int argc, char *argv[]){

    FILE *fp = NULL;
    int i = 0, n_total_palavras = 0;
    char str[MAX_STR];
    int  count = 0;
    char **Words;

    fp = fopen("words.dict", "r");
    if (fp == NULL){
        exit (0);
    }

    while (fscanf(fp,"%s",str) == 1){
        n_total_palavras  ;
    }

    Words = (char **)malloc(n_total_palavras * sizeof (char *));
    if (Words == NULL){
        exit(0);
    }

    for (i = 0; i < n_total_palavras; i  ){
        Words[i] = NULL;
         
    }

    rewind (fp);
    while (fscanf(fp,"%s",str) == 1){
       Words[count] = (char*)malloc((strlen(str) 1) * sizeof(char));
        strcpy(Words[count], str);
        count  ;
    }

    qsort(Words, n_total_palavras, sizeof(Words[0]), compare);

    /* for(i = 0; i < n_total_palavras; i  ){
        printf("%s\n", Words[i]);
    }
    */



    fclose(fp);
    return 0;
}

I'm trying to obtain something like:

4 letters words: 2018
5 letters words: 170
6 letters words: 10
(...)

Any idea on how I should look at this ?

CodePudding user response：

Here's my code implementing what I suggested. It reads the file once, growing the word list as needed. It allocates about twice as much space as before each time more space is needed.

I've simplified the comparison function marginally — but the optimizer probably gets close to what I've written anyway.

The code is currently configured not to print the sorted word list.

/* SO 7400-7509 */

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#define MAX_STR 100

/*
 * Sorting the words first by length and then in alphabetical order
*/

static int compare(const void *a, const void *b)
{
    const char *str_a = *(const char **)a;
    const char *str_b = *(const char **)b;

    int len1 = strlen(str_a);
    int len2 = strlen(str_b);
    if (len1 < len2)
        return -1;
    if (len1 > len2)
        return 1;

    return strcmp(str_a, str_b);
}

int main(int argc, char *argv[])
{
    char str[MAX_STR];
    char **words = 0;
    size_t max_words = 0;
    size_t num_words = 0;
    const char *filename = "words.dict";

    if (argc == 2)
        filename = argv[1];
    else if (argc > 2)
    {
        fprintf(stderr, "Usage: %s [filename]\n", argv[0]);
        exit(EXIT_FAILURE);
    }

    FILE *fp = fopen(filename, "r");
    if (fp == NULL)
    {
        fprintf(stderr, "%s: failed to open file '%s' for reading\n",
                argv[0], filename);
        exit(EXIT_FAILURE);
    }

    while (fscanf(fp, "