Teaser

#include <iostream>
#include <algorithm>
#include <vector>
#include <math.h>
#include <bitset>

const int START = 65, END = 90;

int main()
{
    std::string msg, retMsg;

    for (char ch : msg)
    {
        if (((int)ch < START || (int) ch > END) && ch != ' ')
        {
            retMsg += "\n";
            continue;
        }
        else if(ch != ' ')
        {
            char toAdd = (char)END - ((int)ch - START);
            retMsg += toAdd;
        }
        else retMsg += ' ';
    }

    std::cout << retMsg << std::endl;
}