Thread: Reading files from text and looking for text

I have to write a program that reads in an ASCII text file and looks for a specified set of words in it.
The program should read in all of the words in text file and store them in an array of strings.

Here is my main program below

Code:

#include <stdio.h>



#define MAXCHAR    30
#define MAXWORDS 30

int check_word(char word_list[][MAXCHAR], int num_words, char word[]);

void main(void)


{




FILE *infile = NULL;
    char infilename[MAXWORDS][MAXCHAR];
    char line[MAXCHAR];
    char words[MAXWORDS];

    int i,d,length,c,k=0;

printf("Program to find specific words in a file\n");

    
    while(infile == NULL) {            /* input file name to read open */
        printf("Input filename:");
        scanf("%s",infilename);
        if((infile = fopen(infilename, "r")) == NULL) {
            printf("ERROR: file %s can not be opened!\n",infilename);
        }
    }

    printf("TEST 1\n");

while(fgets(line,MAXCHAR,infile) != NULL) {
    length = strlen(line);
    if(line[length-1] == '\n') {            /* changes new line to null character */
        line[length-1] = '\0';
        length--;
    }
    printf("TEST 2\n");
    check_word(infilename[MAXWORDS][MAXCHAR],MAXWORDS,words[MAXWORDS]);
    printf("TEST 3\n");
    for(d=0;d<MAXWORDS;d++){

    printf("dictionary word %d \"%s\" occurs %d times",d,words[d],i);

}
}





    fclose(infile);


}

Here is my function below

Code:

#define MAXCHAR 30
#define MAXWORDS 30
#define NOT_FOUND -1



int check_word(char word_list[][MAXCHAR], int num_words, char words[])



{


    int i;

    for (i=0; i<num_words;i++)
        if(strncmp(word_list[i],words) == 0){
            return (words[i]);
        }

    return (NOT_FOUND);


}

It has to look for these words

Code:

for
if
else
switch
while
case
break
main
int
float
char
double

in this text file

this file has a bunch of stuff in it. for example,
it has a bunch of characters - main characters maybe. it
also has a bunch of spaces. It doesn't have anything thing like int or
{float} in it - case it did, that would % be double fun. !?!
while this is good, we
should ()switch off else it will be done for good...
btw, this is not a char - char_buff

My program crashes after line 45 (TEST 2). I think the problem is with my subprogram.

Also, there is something wrong with my for loop near the end but I didn't fix it yet because the function doesn't get passed line 45.

You say it "crashes" but how can it even compile? strncmp takes 3 parameters, so clearly if you've actually run the program then you haven't posted the program you've run.

Code:

#define MAXCHAR 30
#define MAXWORDS 30
#define NOT_FOUND -1

int check_word(char word_list[][MAXCHAR], int num_words, char words[])
{
    int i;

    for (i=0; i<num_words;i++)
        if(strncmp(word_list[i],words) == 0){
            return (words[i]);
        }
    return (NOT_FOUND);
}

Also, you're not returning an int but a char*, so NOT_FOUND should be NULL, not -1.

Your main is pretty screwed up too. Look through it carefully. Think. Improve your spacing. Get rid of the pointless blank lines. Think some more.

I was told that the function should return the number of times that the word is found in the text file, so shouldn't it be an int?

In that case, yes. But it's not really counting the number of words, is it. It's just finding the first occurrence. To make it work you would have to (in main) actually READ the words from the file into the word_list array BEFORE every calling the check_word function. Then you'd have to call it for each word in your list of keywords. In check_word you need a separate counter variable, initialized to 0, that you increment every time you find the word. That's the variable you would return.

Some points:

Major errors

infilename should be declared as char infilename[MAXCHAR] (or whatever size you want).

words should be declared as char *words[].

The words for words should be in double-quotes, not single.


Minor (but still important) errors

You should include <string.h> since you're using functions from it.

main should be declared as int main(void) and should return 0 as its last statement.


Other than that, and although you've definitely started thinking a little more, you've really got to tighten down that thinking cap and give it another go. The way you're using infilename is ... insane. Try again.

Hmm, I just found out that I have to read in the words from the text file and then store them into a two dimensional array. I'm sure I'm not doing it right because now my program will not even run. Ok I realized what I did wrong and I'm trying to fix it.

EDIT: So I found out how to read the words from the text file and then store them into a 2D array.

So now it will crash when it reaches the "TEST 2" Marker. I'm not sure how to make the return value for the check_word() function cycle through the different values in the array when I print it out.

EDIT: I put the values into an array of ints. But I still don't know why it's crashing.

Code:

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



#define MAXCHAR    30
#define MAXWORDS 30
#define TEXTWORDS 12

int check_word(char word_list[][MAXCHAR], int num_words, char word[]);

int main(void)
    {
    FILE *infile = NULL;
    FILE *infile2 = NULL;
    char infilename[MAXCHAR];
    char line[MAXCHAR];
    int text[MAXWORDS];
    char *words[MAXWORDS][MAXCHAR];

    int i,d,length,a,c,k=0;

    printf("Program to find specific words in a file\n");

  
    while(infile == NULL) {            /* input file name to read open */
        printf("Input filename:");
        scanf("%s",infilename);
        if((infile = fopen(infilename, "r")) == NULL) {
            printf("ERROR: file %s can not be opened!\n",infilename);
        }
    }

    infile2 = fopen("dictionary.txt","r");
    for(c=0;c<MAXWORDS;c++){
        for(a=0;a<MAXCHAR;a++){
            fscanf(infile2,"%s",words[c][a]);
        }
    }
    printf("TEST 1\n");
    while(fgets(line,MAXCHAR,infile) != NULL) {
        length = strlen(line);
        if(line[length-1] == '\n') {            /* changes new line to null character */
            line[length-1] = '\0';
            length--;
        }
        printf("TEST 2\n");
        for(d=0;d<TEXTWORDS;d++){
         text[d] = check_word(words[MAXWORDS][MAXCHAR],TEXTWORDS,infilename[MAXCHAR]);
        }
        
        printf("TEST 3\n");
        
        for(d=0;d<TEXTWORDS;d++){
            printf("dictionary word %d \"%s\" occurs %d times",d,words[d],text[d]);
        }
    }
    fclose(infile);
    
    return(0);
}

Code:

#define MAXCHAR 30
#define MAXWORDS 30
#define NOT_FOUND -1

int check_word(char word_list[][MAXCHAR], int num_words, char words[])
{
    int i,k;

    for (i=0,k=0; i<num_words,k<num_words;i++,k++)
        if(strncmp(word_list[i],words[i],num_words) == 0){
            return (k);
        }

    return (NOT_FOUND);

}

I just realized that these lines of code don't do what I want them to do.

Code:

printf("TEST 1\n");
    while(fgets(line,MAXCHAR,infile) != NULL) {
     length = strlen(line);
     if(line[length-1] == '\n') {            /* changes new line to null character */
             line[length-1] = '\0';
             length--;
        }

They were supposed to remove newline characters from the text and replace them with '/0' characters. But it still crashes so there still is another problem. I changed it to this:

Code:

printf("TEST 1\n");
    while(fgets(infilename,MAXCHAR,infile) != NULL) {
      length = strlen(infilename);
      if(infilename[length-1] == '\n') {            /* changes new line to null character */
             infilename[length-1] = '\0';
             length--;
        }

EDIT:I'm not even sure if this code is necessary.

Corrected the first problem - try and run this, as it is now.

Code:

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



#define MAXCHAR    30
#define MAXWORDS 30
#define TEXTWORDS 12

int check_word(char word_list[][MAXCHAR], int num_words, char word[]);

int main(void)
    {
    FILE *infile = NULL;
    FILE *infile2 = NULL;
    char infilename[MAXCHAR];
    char line[MAXCHAR];
    int text[MAXWORDS];
    char *words[MAXWORDS][MAXCHAR];

    int i,d,length,a,c,k=0;

    printf("Program to find specific words in a file\n");

     while(infile == NULL) {            //  input file name to read open 
        printf("Input filename:");
        scanf("%s",infilename);
        if((infile = fopen(infilename, "r")) == NULL) {
            printf("ERROR: file %s can not be opened!\n",infilename);
        }
    }

  
/*
 This is the first error I see. You can't store a word, into a space
that is the size of one char. This version should work OK.
*/

  infile2 = fopen("dictionary.txt","r");
   //corrected, and changed to use 'i' for the index variable 
   for(i=0;i<MAXWORDS;i++) {  
        fscanf(infile2,"%s",words[i]);
    }

   /* test it */
   printf("Let's test it:\n");
   for(i=0;i<MAXWORDS;i++)
       printf("%s\n",words[i]);

  
   printf("How'd we do? \n"); getchar(); getchar();


    /* test it and see how it does, to this point */
/*
    printf("TEST 1\n");
    while(fgets(line,MAXCHAR,infile) != NULL) {
        length = strlen(line);
        if(line[length-1] == '\n') {            // changes new line to null character 
            line[length-1] = '\0';
            length--;
        }
        printf("TEST 2\n");
        for(d=0;d<TEXTWORDS;d++){
         text[d] = check_word(words[MAXWORDS][MAXCHAR],TEXTWORDS,infilename[MAXCHAR]);
        }
        
        printf("TEST 3\n");
        
        for(d=0;d<TEXTWORDS;d++){
            printf("dictionary word %d \"%s\" occurs %d times",d,words[d],text[d]);
        }
    }
*/
    fclose(infile);
    
    return(0);
}