如何将文本文件中的单词存储到数组中？

Question

I'm trying to read a text file called "olaola.dict", some sort of a dictionary, that currently holds 10 words each with 5 letters and store the words into an array of strings. I'm using a char** pointer that points to an array of pointers in which each pointer points to a word from the dictionary.

So far, I've developed this code. It is printing the last 7 words correctly, but not the first three. The code is the following:

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

#define ROW 10  /* 10 words */
#define COL 6  /* 5 letters in each word + Null terminator*/

int main(void) {
  int i, j;
  FILE *fp = NULL;
  char **ptr = NULL;

  ptr = (char**)malloc(ROW * sizeof(char*));
  fp = fopen("olaola.dict","r");
  for (i=0 ; i < 15; i++) {
    if ((ptr[i] = malloc(sizeof(char) * COL)) == NULL) {
      printf("unable to allocate memory \n");
          return -1;
    }
    fscanf(fp, "%s", ptr[i]);
  }

  for(i = 0; i < ROW; i++){
    printf("Word %d:%s\n", i+1,ptr[i]);
  }

  for (i=0 ; i < ROW; i++)
    free(ptr[i]);
  free(ptr);
  fclose(fp);

  return 0;
}
/*
   ptr[]                0   1   2   3   4   5   6   
    +--------+        +---+---+---+---+---+---+---+
    |      --|------->| w | o | r | d | 0 | 0 |\0 |
    +--------+        +---+---+---+---+---+---+---+
    |      --|------->| w | o | r | d | 0 | 1 |\0 |
    +--------+        +---+---+---+---+---+---+---+
    |      --|------->| w | o | r | d | 0 | 2 |\0 |
    +--------+        +---+---+---+---+---+---+---+
    |      --|------->| w | o | r | d | 0 | 3 |\0 |
    +--------+        +---+---+---+---+---+---+---+
    |      --|------->| w | o | r | d | 0 | 4 |\0 |
    +--------+        +---+---+---+---+---+---+---+


*/

The output is:

Word 1:[p:�
Word 2:0[p:�
Word 3:P[p:�
Word 4:Carlo
Word 5:Andre
Word 6:MESSI
Word 7:Arroz
Word 8:Doces
Word 9:Carro
Word 10:Tevez

Here is also the text file olaola.dict

lista
         
    Sabes    ontem     Carlo
Andre

MESSI

Arroz         Doces             Carro            Tevez

As you can see, there is no specific position for the words to be. What would be the correct way to solve this problem? (In another note, would it be wiser and more efficient to use a 2D array, even though the dictionary can have like 5k words?)

Answer 1

you problem is in this line

for (i=0 ; i < 15; i++) {

it's supposed to be:

for (i=0 ; i < ROW; i++)

because you should allocate till ptr[9] , but you are allocating till ptr[14] which will produce undefined behavior as the size of the array = 10

Answer 2

I noticed that the first for loop goes from zero to 14 instead of from zero to 9. This means that the code writes beyond the boundaries of the array. I assume that this writes to the memory being allocated for the first 3 words and this is the reason why you see the wrong values for these words. Correct the for loop and see if this solves the issue.