HardenedBSD/games/caesar/caesar.6
Ruslan Ermilov 46eea498da mdoc(7) police: Change -filled displays (which just happen
to be the same as -ragged in the current implementation) to
-ragged.  With mdocNG, -filled displays produce the correct
output, formatted and justified to both margins.
2001-02-07 13:45:30 +00:00

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.\" Copyright (c) 1989, 1991, 1993
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.\" @(#)caesar.6 8.2 (Berkeley) 11/16/93
.\" $FreeBSD$
.\"
.Dd November 16, 1993
.Dt CAESAR 6
.Os
.Sh NAME
.Nm caesar
.Nd decrypt caesar ciphers
.Sh SYNOPSIS
.Nm
.Op Ar rotation
.Sh DESCRIPTION
The
.Nm
utility attempts to decrypt caesar ciphers using English letter frequency
statistics.
.Nm Caesar
reads from the standard input and writes to the standard output.
.Pp
The optional numerical argument
.Ar rotation
may be used to specify a specific rotation value.
.Pp
The frequency (from most common to least) of English letters is as follows:
.Pp
.Bd -ragged -offset indent
ETAONRISHDLFCMUGPYWBVKXJQZ
.Ed
.Pp
Their frequencies as a percentage are as follows:
.Pp
.Bd -ragged -offset indent
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).
.Ed
.Pp
Rotated postings to
.Tn USENET
and some of the databases used by the
.Xr fortune 6
program are rotated by 13 characters.