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+/*
+ * Copyright (c) 1990, 1993
+ * The Regents of the University of California. All rights reserved.
+ *
+ * This code is derived from software contributed to Berkeley by
+ * Chris Torek.
+ *
+ * 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. All advertising materials mentioning features or use of this software
+ * must display the following acknowledgement:
+ * This product includes software developed by the University of
+ * California, Berkeley and its contributors.
+ * 4. Neither the name of the University 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 REGENTS 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 REGENTS 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.
+ */
+
+#if defined(LIBC_SCCS) && !defined(lint)
+static char sccsid[] = "@(#)div.c 8.1 (Berkeley) 6/4/93";
+#endif /* LIBC_SCCS and not lint */
+
+#include <stdlib.h> /* div_t */
+
+div_t
+div(num, denom)
+ int num, denom;
+{
+ div_t r;
+
+ r.quot = num / denom;
+ r.rem = num % denom;
+ /*
+ * The ANSI standard says that |r.quot| <= |n/d|, where
+ * n/d is to be computed in infinite precision. In other
+ * words, we should always truncate the quotient towards
+ * 0, never -infinity.
+ *
+ * Machine division and remainer may work either way when
+ * one or both of n or d is negative. If only one is
+ * negative and r.quot has been truncated towards -inf,
+ * r.rem will have the same sign as denom and the opposite
+ * sign of num; if both are negative and r.quot has been
+ * truncated towards -inf, r.rem will be positive (will
+ * have the opposite sign of num). These are considered
+ * `wrong'.
+ *
+ * If both are num and denom are positive, r will always
+ * be positive.
+ *
+ * This all boils down to:
+ * if num >= 0, but r.rem < 0, we got the wrong answer.
+ * In that case, to get the right answer, add 1 to r.quot and
+ * subtract denom from r.rem.
+ */
+ if (num >= 0 && r.rem < 0) {
+ r.quot++;
+ r.rem -= denom;
+ }
+ return (r);
+}
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