บูทฟอร์ด caesar

//Decrypt Aj.Sang comsecurity
#include <iostream>
#include <string>

void encrypt( std::string &iostr , int key )
{
    key %= 26;
    int ch;

    for( auto &it : iostr )
    {
        ch = tolower(it) + key;
        if( ch > 'z' )
            ch -= 26;
        it = ch;
    }
}

int main()
{
    std::string source = "TJUAHJFAHBUTAKHAEISTGINTEDJZPDEVTBDIFSIXJFXVWDZPZPTHZAHJZDGZBHFTEKEZTNWPDGPGBTHZTFEINTZPDJUICHGXAZXBHAGIJZDJXXNIRTBHAHBUTVHBZICWTEZTBJTXBIVT";

    for(int i=26;i>=0;i--){
        std::cout << std::endl;
        encrypt( source , i );
        std::cout << source << std::endl;
    }


    return 0;
}