Word finder not outputting as expected

Question

the code is supposed to output all possible word combinations without any whitespace but with this method, it gives me whitespace

Here's the code:

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

int main() {
    char letters[6];
    int on = 0;
    int results;

    printf("input the words all together: ");
    scanf("%s", letters);

    if (strlen(letters) == 6) {
        for (int i = 0; i <= 6; i++) {
            for (int j = 0; j <= 6; j++) {
                for (int k = 0; k <= 6; k++) {
                    for (int l = 0; l <= 6; l++) {
                        for (int m = 0; m <= 6; m++) {
                            for (int n = 0; n <= 6; n++) {
                                char wordNow[6] = {
                                    letters[i], 
                                    letters[j], 
                                    letters[k], 
                                    letters[l], 
                                    letters[m], 
                                    letters[n]
                                };
                                printf("%s\n", wordNow);
                                results = results+1;
                            }
                        }
                    }
                }
            }
        }
    }

    printf("%d", results);

    return 0;
}

This code is supposed to take in 6 characters and produce all possible combinations using those characters. When I use that method, the combinations end up repeating and gives me whitespace.

My old method that works but adds whitespace is:

printf("%c %c %c %c %c %c\n", 
       letters[i], letters[j], letters[k], 
       letters[l], letters[m], letters[n]);

If anyone could help, I would appreciate it.

Lessons (1) NEVER skimp on buffer size; (2) `scanf ("%s", letters);` is no safer than `gets()`, see [Why gets() is so dangerous it should never be used!](https://stackoverflow.com/q/1694036/3422102). You must ALWAYS use a *field-width* modifier when filling a character array (e.g. `scanf ("%5s", letters)`) and (3) you must ALWAYS validate input succeeded (e.g. `if (scanf ("%5s", letters) != 1) return 1;` (of course adjust the numbers when you fix the problem with Rule (1) above). — David C. Rankin, Jul 05 '21 at 01:30

score 3 · Accepted Answer · answered Jul 05 '21 at 01:26

3

wordNow is not null terminated, leading to the output you are seeing. Also, results is not initialized.

answered Jul 05 '21 at 01:26

Brady Dean

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2

(you caught the main errors, but expanding a bit with further explanation probably wouldn't hurt...) – David C. Rankin Jul 05 '21 at 01:27

ggorlen · Answer 2 · 2021-07-05T01:31:57.243

You'll need to null terminate your string if you plan to print it, since printf will keep iterating over the characters in the string until it hits the null terminator:

char wordNow[7] = {
    letters[i], 
    letters[j], 
    letters[k], 
    letters[l], 
    letters[m], 
    letters[n], 
    '\0' // <-- added
};

int results; should be int result = 0; as Brady points out.

You might want to run your loops up to < rather than <= if you want to omit null terminators.

Word finder not outputting as expected

2 Answers2