Here are some applets which I write
You can search the setences of Shakespheare's works
$ cd inserve-index-search-engine
$ g++ main.cpp
$ ./a.out
> to be or not to be
Crack the enigma
$ cd enigma
$ unzip dic.zip
$ gcc main.c
$ ./a.out
Input Plugboard, RringSetting, Ciphertext, known plaintext, the left Gear number
PO LM IU JK NH YT GB VF RE DC
TIP
MNZUXZEZWCAYJVTODAEFBVKYXW
CRYPTO
1
A executor of LC-3 machine code
$ cd LC3-Executor
$ g++ main.cpp && ./a.out
> 0011000000000000
0101010000100000
0001010010110100
0000100000000001
0001100010100001
1111000000100101