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+/* Arithmetic.
+   Copyright (C) 2001 Free Software Foundation, Inc.
+   Written by Bruno Haible <haible@clisp.cons.org>, 2001.
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 2, or (at your option)
+   any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program; if not, write to the Free Software Foundation,
+   Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */
+
+#ifndef _GCD_H
+#define _GCD_H
+
+#ifndef PARAMS
+# if __STDC__ || defined __GNUC__ || defined __SUNPRO_C || defined __cplusplus || __PROTOTYPES
+#  define PARAMS(args) args
+# else
+#  define PARAMS(args) ()
+# endif
+#endif
+
+/* Return the greatest common divisor of a > 0 and b > 0.  */
+extern unsigned int gcd PARAMS ((unsigned int a, unsigned int b));
+
+#endif /* _GCD_H */