实施交流计数器

Question

I wrote ac program to count the number of time the word "printf" occurs in a specific file (here "document.c"). "document.c" has multiple lines of code. What I have done is I started with a while loop to iterate over every lines of the file and then I am reading the characters of each lines inside the for loop by using the function strstr.

It does not print anything with my current code. Moreove, I think there is some other minor issues because in an older version it used to print but not correctly, it printed a number much more larger than the actual number of "printf" in the document.

I am also novice in c.thank you!

int counter() {
    FILE * filePointer;
    filePointer = fopen("document.c", "r");
    int counter = 0;
    char singleLine[200];

    while(!feof(filePointer)){
        fgets(singleLine, 200, filePointer);
        for (int i = 0; i < strlen(singleLine); i++){
            if(strstr(singleLine, "printf")){
                counter++;
            }
        }
    }
    fclose(filePointer);
    printf("%d",counter);
    return 0;
}

Answer 1

You're iterating over each character in the input line, and then asking if the string "printf" appears anywhere in the line. If the line contains 5 characters, you'll ask this 5 times; if it contains 40 characters, you'll ask this 40 times.

Assuming that you're trying to cover the case where "printf" can appear more than once on the line, look up what strstr() returns, and use that to adjust the starting position of the search in the inner loop (which shouldn't iterate over each character, but should loop while new "hits" are found).

(Note to up-voters: I'm answering the question, but not providing code because I don't want to do their homework for them.)