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authorJordan K. Hubbard <jkh@FreeBSD.org>1994-11-22 10:58:58 +0000
committerJordan K. Hubbard <jkh@FreeBSD.org>1994-11-22 10:58:58 +0000
commit140932d6d85b561ad06abe5006a5e973a7713c45 (patch)
treebe1d2469fd1ab2ab0df6164fbc91fb7bbbdd80f5 /gnu/usr.bin/groff/libgroff/prime.cc
parent324ec40db3d437d18da21aa07a7ae4d4ecd9c157 (diff)
Tell stupid users to write the bootcode.upstream/2.0_cvsrelease/2.0_cvs
This commit was manufactured to restore the state of the 2.0-RELEASE image. Releases prior to 5.3-RELEASE are omitting the secure/ and crypto/ subdirs.
Diffstat (limited to 'gnu/usr.bin/groff/libgroff/prime.cc')
-rw-r--r--gnu/usr.bin/groff/libgroff/prime.cc28
1 files changed, 28 insertions, 0 deletions
diff --git a/gnu/usr.bin/groff/libgroff/prime.cc b/gnu/usr.bin/groff/libgroff/prime.cc
new file mode 100644
index 000000000000..531856c2a59a
--- /dev/null
+++ b/gnu/usr.bin/groff/libgroff/prime.cc
@@ -0,0 +1,28 @@
+extern "C" {
+#include <math.h>
+}
+
+int is_prime(unsigned n)
+{
+ if (n <= 3)
+ return 1;
+ if (!(n & 1))
+ return 0;
+ if (n % 3 == 0)
+ return 0;
+ unsigned lim = unsigned(sqrt((double)n));
+ unsigned d = 5;
+ for (;;) {
+ if (d > lim)
+ break;
+ if (n % d == 0)
+ return 0;
+ d += 2;
+ if (d > lim)
+ break;
+ if (n % d == 0)
+ return 0;
+ d += 4;
+ }
+ return 1;
+}