1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
|
NAME
comb - combinatorial number
SYNOPSIS
comb(x, y)
TYPES
x integer
y integer
return integer
DESCRIPTION
Return the combinatorial number C(x,y) which is defined as:
x!
---------
y!*(x-y)!
This function computes the number of combinations in which y things
may be chosen from x items ignoring the order in which they are chosen.
EXAMPLE
; print comb(7,3), comb(7,4), comb(7,5), comb(3,0), comb(0,0)
35 35 21 1 1
; print comb(2^31+1,2^31-1)
2305843010287435776
LIMITS
x >= y >= 0
y < 2^24
x-y < 2^24
LINK LIBRARY
void zcomb(ZVALUE x, ZVALUE y, ZVALUE *res)
SEE ALSO
fact, perm, randperm
## Copyright (C) 1999-2006 Landon Curt Noll
##
## Calc is open software; you can redistribute it and/or modify it under
## the terms of the version 2.1 of the GNU Lesser General Public License
## as published by the Free Software Foundation.
##
## Calc 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 Lesser General
## Public License for more details.
##
## A copy of version 2.1 of the GNU Lesser General Public License is
## distributed with calc under the filename COPYING-LGPL. You should have
## received a copy with calc; if not, write to Free Software Foundation, Inc.
## 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
##
## Under source code control: 1994/10/20 04:03:02
## File existed as early as: 1994
##
## chongo <was here> /\oo/\ http://www.isthe.com/chongo/
## Share and enjoy! :-) http://www.isthe.com/chongo/tech/comp/calc/
|
