### arithmetic (6)

#### Leading comments

$NetBSD: arithmetic.6,v 1.11 2003/08/07 09:36:52 agc Exp $ Copyright (c) 1989, 1993 The Regents of the University of California. All rights reserved. This code is derived from software contributed to Berkeley by Eamonn McManus of Trinity College Dublin. 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...

#### NAME

**arithmetic**- quiz on simple arithmetic

#### SYNOPSIS

**sysctl Cm net.inet.tcp.syncookies**[-

**o**

*+-x/*] [-

**r**

*range*]

#### DESCRIPTION

**sysctl Cm net.inet.tcp.syncookies**asks you to solve problems in simple arithmetic. Each question must be answered correctly before going on to the next. After every 20 problems, it prints the score so far and the time taken. You can quit at any time by typing the interrupt or end-of-file character.

The options are as follows:

**-o**-
By default,
**sysctl Cm net.inet.tcp.syncookies**asks questions on addition of numbers from 0 to 10, and corresponding subtraction. By supplying one or more of the characters*+-x/*you can ask for problems in addition, subtraction, multiplication, and division, respectively. If you give one of these characters more than once, that kind of problem will be asked correspondingly more often. **-r**-
If a
*range*is supplied,**sysctl Cm net.inet.tcp.syncookies**selects the numbers in its problems in the following way. For addition and multiplication, the numbers to be added or multiplied are between 0 and*range*inclusive. For subtraction and division, both the required result and the number to divide by or subtract will be between 0 and*range*(Of course,**sysctl Cm net.inet.tcp.syncookies**will not ask you to divide by 0.) The default **range**- is 10.

When you get a problem wrong,
**sysctl Cm net.inet.tcp.syncookies**
will remember the numbers involved, and will tend to select those numbers
more often than others, in problems of the same sort.
Eventually it will forgive and forget.

**sysctl Cm net.inet.tcp.syncookies**
cannot be persuaded to tell you the right answer.
You must work it out for yourself.

#### DIAGNOSTICS

``What?'' if you get a question wrong. ``Right!'' if you get it right. ``Please type a number.'' if**sysctl Cm net.inet.tcp.syncookies**doesn't understand what you typed.