# cryptanalysis, substitution cipher

A substitution cipher exchanges letters, i.e. applies a permutation to the set of letters of the text.

You may try cryptanalyzing the following texts, which were obtained from an english text by a substitution cipher:

```qfl hcvps px v answlcezk ncjvs; pq xqvcqx qfl bpszql rnz jlq zt ps qfl bncspsj vsw wnlx snq xqnt zsqpk rnz jlq qn qfl neepgl. -- cnhlcq ecnxq
```

`coxbx tbx cvk cdgxr di t gti'r adhx voxi ox rokqau ikc rnxpqatcx: voxi ox pti'c thhkbu dc, tiu voxi ox pti. -- gtby cvtdi`

```probabilities of letters in English text:
a .082
b .015
c .028
d .043
e .127
f .022
g .020
h .061
i .070
j .002
k .008
l .040
m .024
n .067
o .075
p .019
q .011
r .060
s .063
t .091
u .028
v .010
w .023
x .001
y .020
z .001

sorted:
e .127 vowel
t .091
a .082 vowel
o .075 vowel
i .070 vowel
n .067
s .063
h .061
r .060
d .043
l .040
c .028
u .028 vowel
m .024
w .023
f .022
g .020
y .020
p .019
b .015
q .011
v .010
k .008
j .002
x .001
z .001
```

the ciphertext:

your guess, type pairs of letters which you think correspond, i.e. xaybzc would mean that you decode x,y,z as a,b,c, respectively:

created by A. Betten, August 23, 2003, last change August 23, 2003