/* Encryption OTP OTP stands for one time pad. It is an encryption method that uses a key that is meant to be destroyed after a single decryption usage. It is said to be a very solid encryption method. However, it is unsuitable for many pratical use mainly due to the fact it needs a key that is as long as the message. A 100 characters message needs a 100 characters key or more. Key The key is composed of randomly generated characters, typically alphabetical +/- digits characters, but we could use the full char/byte range of values instead and make a full range 256x256 table also for full char/byte encryption. Table In this example, we need a table that links an encrypted message character to a key character and finally to a decrypted character. */ #include #include #include #include using namespace std; array char_set; map>table; map>table2; void init_char_set(){ int cs_index=0; for(char c='a';c<='z';c++,cs_index++) char_set[cs_index]=c; for(char c='0';c<='9';c++,cs_index++) char_set[cs_index]=c; for(auto c:char_set) cout<r_map{}; mapr2_map{}; for(int col=0;col<36;col++){ r_map[char_set[(36+col-row)%36]]=char_set[col]; r2_map[char_set[col]]=char_set[(36+col-row)%36]; } table[char_set[row]]=r_map; table2[char_set[row]]=r2_map; for(auto c:char_set) cout<

OTP - one time pad encryption