Copyright (c) 1989 The Regents of the University of California.
All rights reserved.
%sccs.include.redist.man%
@(#)caesar.6 5.3 (Berkeley) 11/11/90
All rights reserved.
%sccs.include.redist.man%
@(#)caesar.6 5.3 (Berkeley) 11/11/90
CAESAR 6 ""
C 7 NAME
caesar - decrypt caesar cyphers
SYNOPSIS
caesar [
rotation ]
DESCRIPTION
The
caesar utility attempts to decrypt caesar cyphers using English letter frequency
statistics.
Caesar reads from the standard input and writes to the standard output.
The optional numerical argument rotation may be used to specify a specific rotation value.
The frequency (from most common to least) of English letters is as follows:
ETAONRISHDLFCMUGPYWBVKXJQZ
Their frequencies as a percentage are as follows:
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).
Rotated postings to USENET and some of the databases used by the fortune (6) program are rotated by 13 characters.