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#include <stdio.h>
#include <stdlib.h>
#include <stdbool.h>
#include <assert.h>

/**
 * Malloc a string
 * Fill hte string with the passed character, repeated the number
 * of times
 */
char* repeat_character(char char_to_repeat, int num_times_to_repeat) {
    // possible bug: losing the original address during iteration
    // best fix: store a copy of the original address
    char* const output_str = malloc((num_times_to_repeat + 1)
            * sizeof(*output_str));
    char* iterate_str = output_str;
    for (int i = 0; i < num_times_to_repeat; i++) {
        *iterate_str = char_to_repeat;
        iterate_str += 1;
    }
    *iterate_str = '\0';
    // this could lead to off by one errors
    // output_str -= num_times_to_repeat;
    return output_str;
}

int main(int argc, char* argv[]) {
    char* f_string = repeat_character('f', 5);
    // possible bug: freeing f_string before we print it
    printf("5 f's %s\n", f_string);
    free(f_string); 
    
    char* q_string = repeat_character('q', 7);
    printf("7 q's %s\n", q_string);
    // possible bug: double free if we try to free f_string again
    free(q_string);
    return EXIT_SUCCESS;
}
/* vim: set tabstop=4 shiftwidth=4 fileencoding=utf-8 noexpandtab: */

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