NetBSD/games/caesar/caesar.6

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.\" Copyright (c) 1989 The Regents of the University of California.
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.\" @(#)caesar.6 5.3 (Berkeley) 11/11/90
.\"
.TH CAESAR 6 "November 11, 1990"
.UC 7
.SH NAME
caesar \- decrypt caesar cyphers
.SH SYNOPSIS
.B caesar
[
.B rotation
]
.SH DESCRIPTION
The
.I caesar
utility attempts to decrypt caesar cyphers using English letter frequency
statistics.
.I Caesar
reads from the standard input and writes to the standard output.
.PP
The optional numerical argument
.I rotation
may be used to specify a specific rotation value.
.PP
The frequency (from most common to least) of English letters is as follows:
.sp
.RS
ETAONRISHDLFCMUGPYWBVKXJQZ
.RE
.PP
Their frequencies as a percentage are as follows:
.sp
.RS
E(13), T(10.5), A(8.1), O(7.9), N(7.1), R(6.8), I(6.3), S(6.1), H(5.2),
D(3.8), L(3.4), F(2.9), C(2.7), M(2.5), U(2.4), G(2), P(1.9), Y(1.9),
W(1.5), B(1.4), V(.9), K(.4), X(.15), J(.13), Q(.11), Z(.07).
.RE
.PP
Rotated postings to USENET and some of the databases used by the
.IR fortune (6)
program are rotated by 13 characters.