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/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License, Version 1.0 only
* (the "License"). You may not use this file except in compliance
* with the License.
*
* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
* or http://www.opensolaris.org/os/licensing.
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
* If applicable, add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your own identifying
* information: Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*/
/*
* Copyright 2005 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*/
/* Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T */
/* All Rights Reserved */
#pragma ident "%Z%%M% %I% %E% SMI"
/* factor COMPILE: cc -O factor.c -s -i -lm -o factor */
/*
* works up to 14 digit numbers
* running time is proportional to sqrt(n)
* accepts arguments either as input or on command line
* 0 input terminates processing
*/
double modf(), sqrt();
double nn, vv;
double huge = 1.0e14;
double sq[] = {
10, 2, 4, 2, 4, 6, 2, 6,
4, 2, 4, 6, 6, 2, 6, 4,
2, 6, 4, 6, 8, 4, 2, 4,
2, 4, 8, 6, 4, 6, 2, 4,
6, 2, 6, 6, 4, 2, 4, 6,
2, 6, 4, 2, 4, 2,10, 2,
};
void try(double);
int
main(int argc, char *argv[])
{
int test = 1;
int ret;
int j;
double junk, temp;
double fr;
double ii;
if(argc > 2){
printf("Usage: factor number\n");
exit(1);
}
if(argc == 2){
ret = sscanf(argv[1], "%lf", &nn);
test = 0;
printf("%.0f\n", nn);
goto start;
}
while(test == 1){
ret = scanf("%lf", &nn);
start:
if((ret<1) || (nn == 0.0)){
exit(0);
}
if((nn<0.0) || (nn>huge)){
printf("Ouch!\n");
continue;
}
fr = modf(nn, &junk);
if(fr != 0.0){
printf("Not an integer!\n");
continue;
}
vv = 1. + sqrt(nn);
try(2.0);
try(3.0);
try(5.0);
try(7.0);
ii = 1.0;
while(ii <= vv){
for(j=0; j<48; j++){
ii += sq[j];
retry:
modf(nn/ii, &temp);
if(nn == temp*ii){
printf(" %.0f\n", ii);
nn = nn/ii;
vv = 1 + sqrt(nn);
goto retry;
}
}
}
if(nn > 1.0){
printf(" %.0f\n", nn);
}
printf("\n");
}
return (0);
}
void
try(double arg)
{
double temp;
retry:
modf(nn/arg, &temp);
if(nn == temp*arg){
printf(" %.0f\n", arg);
nn = nn/arg;
vv = 1 + sqrt(nn);
goto retry;
}
}
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