/*
 * Copyright 2002 Massachusetts Institute of Technology
 *
 * Permission to use, copy, modify, and distribute this software and
 * its documentation for any purpose and without fee is hereby
 * granted, provided that both the above copyright notice and this
 * permission notice appear in all copies, that both the above
 * copyright notice and this permission notice appear in all
 * supporting documentation, and that the name of M.I.T. not be used
 * in advertising or publicity pertaining to distribution of the
 * software without specific, written prior permission.  M.I.T. makes
 * no representations about the suitability of this software for any
 * purpose.  It is provided "as is" without express or implied
 * warranty.
 * 
 * THIS SOFTWARE IS PROVIDED BY M.I.T. ``AS IS''.  M.I.T. DISCLAIMS
 * ALL EXPRESS OR IMPLIED WARRANTIES WITH REGARD TO THIS SOFTWARE,
 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT
 * SHALL M.I.T. BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#include <err.h>
#include <stdio.h>
#include <gmp.h>

int
main(int argc, char **argv)
{
	int pow;
	mpz_t num, den, rem, tmp;

	if (argc != 2) {
		errx(1, "must supply number to factor as an argument");
	}

	if (mpz_init_set_str(num, argv[1], 10) != 0) {
		errx(1, "mpz_init_set_str(num) error");
	}
	mpz_init(den);
	mpz_init(rem);
	mpz_init(tmp);

	while (mpz_inp_str(den, NULL, 10) > 0) {
		if (mpz_cmp(num, den) < 0)
			return 0;
		pow = 0;
		mpz_set(tmp, num);

		/* Inefficient but easy to follow. */
		mpz_mod(rem, num, den);
		while (mpz_cmp_ui(rem, 0) == 0) {
			pow++;
			mpz_divexact(tmp, tmp, den);
			mpz_mod(rem, tmp, den);
		}
		if (pow) {
			mpz_out_str(NULL, 10, den);
			if (pow > 1)
				printf("**%d", pow);
			printf("\n");
		}
	}
	return 0;
}