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csortingbubble-sorttxt

How can I read a txt file to an array and sorting in ascending order?


I have a txt file includes 10000 passwords in it.I am trying to sort the passwords by length.Here is my function:

void bubbleSortASC(){
    int n = 9999;
    int i,j ;
    char pw[n];
    char temp;
    FILE* fp;
    fp = fopen("C:\\Users\\inanm\\Desktop\\project-work-2018555459\\10-million-password-list-top\\10000.txt", "r");
    //fgets(pw, n , fp);
    while(!feof(fp)){
        fgets(pw, n , fp);
       //printf("%s",pw);
    }
    for(i = 0; i < n-1;i++) {
        for(j = i+1; j < n; j++){
            if(strlen(pw[i]) > strlen(pw[j])){
                strcpy(temp,pw[i]);
                strcpy(pw[i],pw[j]);
                strcpy(pw[j],temp);
            }
        }
    }
    fclose(fp);
printf("Ascending order of first 10 passwords are : \n");
for (i = 0; i < 10; i++){
        printf("%s ", pw[i]);
    }
     printf("\n");
        
}

I've got no error but my output is empty.Can you help me to find the problem


Solution

  • This would do

    
    void bubbleSortASC() {
        const int lines = 9999;     //< number of words in the file
        const int max_width = 128;  //< max width of a word
    
        char pw[lines][max_width];  //< array of words
    
        FILE* fp;
        fp = fopen("words.txt", "r");
        int curr = 0;
        while (!feof(fp)) {
            fgets(pw[curr++], max_width, fp);
        }
        fclose(fp);
    
        char* sorted[lines];        //< array of char* will be in a sorted order
        for (int i = 0; i < lines; i++) sorted[i] = pw[i];
    
        // the bubble sort
        for (int i = 0; i < lines - 1; i++) {
            for (int j = 0; j < lines - i - 1; j++) {
                if (strlen(sorted[j]) > strlen(sorted[j+1])) {
                    char* tmp = sorted[j];
                    sorted[j] = sorted[j+1];
                    sorted[j+1] = tmp;
                }
            }
        }
    
        printf("Ascending order of first 10 passwords are : \n");
        for (int i = 0; i < 10; i++) {
            printf("%s", sorted[i]);
        }
        printf("\n");
    
    }