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Diffstat (limited to 'c_src/arlamath.c')
-rw-r--r-- | c_src/arlamath.c | 69 |
1 files changed, 69 insertions, 0 deletions
diff --git a/c_src/arlamath.c b/c_src/arlamath.c new file mode 100644 index 0000000..99ff6f6 --- /dev/null +++ b/c_src/arlamath.c @@ -0,0 +1,69 @@ +/* + * Copyright (c) 2002 Kungliga Tekniska Högskolan + * (Royal Institute of Technology, Stockholm, Sweden). + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * + * 3. Neither the name of the Institute nor the names of its contributors + * may be used to endorse or promote products derived from this software + * without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS 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. + */ + +/* + * a collection of math functions + */ + +/* $Id: arlamath.c,v 1.1 2002/05/12 16:00:24 lha Exp $ */ + +#include "arlamath.h" + +int +arlautil_isprime(int p) +{ + int q,i; + for(i=2 ; i < p; i++) { + q = p/i; + + if(i*q == p) + return 0; + if(i*i > p) + return 1; + } + return 1; +} + +int +arlautil_findprime(int p) +{ + if(p % 2 == 0) { + p++; + } + + while(!arlautil_isprime(p)) { + p+=2; + } + return p; +} + |