Generate passwords from list in pairs of two

Question

I've recently found an old TrueCrypt volume file of mine, but after an hour of trying out different passwords I haven't found the right one. I know for a fact that I used a combination of old passwords, but it would take a very long time to try all combinations by hand. I've tried different programs (such as Crunch) to construct a wordlist, but all they do is to generate combinations of every single entry in the .txt-file.

So my question is: does anyone know of a program that could combine all the entries in the file, but only in pairs of two?

For example:

String 1 = hello

String 2 = bye

output =

hellobye

byehello

Answer 1

Under windows, the following command will combine all combinations of two passwords into a new file, using a plain text file as input with line-seperated passwords.

for /F "tokens=*" %i in (passwords.txt) do @(
    for /F "tokens=*" %j in (passwords.txt) do
        @echo %i%j
)>> combinations.txt

Answer 2

Sample wordlist: cat list.txt

a
b
c
d

Script: cat list.py:

words = []
file = open('list.txt', 'r')
for word in file.readlines():
    words.append(word.replace('\n', ''))

#i - 1 is to prevent extending past the end of the list on last try
for i in range(len(words) - 1):
    #i + 1 is to prevent "wordword"
    for j in range(i + 1, len(words)):
        print words[i] + words[j]
        print words[j] + words[i]

Output: python list.py

ab
ba
ac
ca
ad
da
bc
cb
bd
db
cd
dc