C Coding: Create Char Array, Print, Reorganize, and Print Again - c

Question

I would like to create a char array, print it, reorganize it, and then reprint it in C. Here's what I have so far:
#include <math.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
int main(){
int i = 0;
int j = 0;
char k[4][2];
char thing[1][1];
strcpy(k[0] , "A");
strcpy(k[1] , "B");
strcpy(k[2] , "C");
strcpy(k[3] , "D");
printf("\nThe original order is: \n");
for (int i = 0; i < 4; i++) { // fill
printf("%s,", k[i]);
}
printf("\nThe reordering is: \n");
for (int i = 0; i < 4; i++) { // reorder
strcpy(thing[0], k[i]);
j = (int)(i + rand() / (RAND_MAX / (5 - i)) );
strcpy(k[i], k[j]);
strcpy(k[j], thing[0]);
printf("%s,", k[i]); // print
}
return(0);
}
Here's my Terminal Output. There are no warnings, just the abort.
mac% clang thing.c -o thing
mac% ./thing
The original order is:
A,B,C,D,
The reordering is:
zsh: abort ./thing

Answer 1

I figured it out! Here's the solution I came up with:
#include <math.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
int main(){
int i = 0;
int j = 0;
char k[4] = "ABCD";
char thing[1] = "O";
printf("\nThe original order is: \n");
for (int i = 0; i < 4; i++) { // fill
printf("%c,", k[i]);
}
printf("\nThe reordering is: \n");
for (int i = 0; i < 4; i++) { // reorder
thing[0]= k[i];
j = (int)(i + rand() / (RAND_MAX / (4 - i)) );
k[i]= k[j];
k[j]= thing[0];
printf("%c,", k[i]); // print
}
return(0);
}
And the output is
The original order is:
A,B,C,D,
The reordering is:
A,B,D,C,%