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

	// Function Prototypes
	void printWrapper(char str[]);
	void printAll(char str[], char perm[], int used[], int k, int n);

	// Calls recursive permutation function
	void printWrapper(char str[]) {
		int len = strlen(str);
		char perm[len + 1];
		perm[len] = '\0';
		int used[len];
		for (int i = 0; i < len; i++) {
			used[i] = 0;
		}
		printAll(str, perm, used, 0, len);
	}

	// Recursively creates/ prints all permutations of char[] str
	void printAll(char str[], char perm[], int used[], int k, int n) {
		if (k == n) { // Base case - Stops when k reaches length of str
			printf("%s\n", perm);
			return;
		}

		for (int i = 0; i < n; i++) {
			if (!used[i]) {
				used[i] = 1;
				perm[k] = str[i];
				printAll(str, perm, used, k + 1, n);
				used[i] = 0;
			}
		}

		return;
	}

	int main(void) {
		char str[] = "CAT";
		printWrapper(str);
		return 0;
	}