A simple C++ console app that will make any given string into a box.

boxify.cpp

/*
 *       DO WHAT THE FUCK YOU WANT TO PUBLIC LICENSE 
 *                   Version 2, December 2004 
 *
 * Copyright (C) 2018 Mitca Dumitru 
 *
 * Everyone is permitted to copy and distribute verbatim or modified 
 * copies of this license document, and changing it is allowed as long 
 * as the name is changed. 
 *
 *           DO WHAT THE FUCK YOU WANT TO PUBLIC LICENSE 
 *  TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION 
 *
 * 0. You just DO WHAT THE FUCK YOU WANT TO.
*/

#include <cctype>
#include <iostream>
#include <fstream>

enum class line : int {
    hor = 1,
    hor_rev = 2,
    ver = 3,
};

std::string makeLine(std::string& strIn, line l, int spaces = 0) {
    std::string line_ret;
    switch(l) {
        case line::hor: {
            for(size_t i = 0; i < strIn.length(); i++) {
                line_ret.push_back(toupper(strIn[i]));
                line_ret.push_back(' ');
            }
            line_ret.push_back('\n');
            return line_ret;
        }
        case line::hor_rev: {
            for(int i = strIn.length() - 1; i >= 0; i--) {
                line_ret.push_back(toupper(strIn[i]));
                line_ret.push_back(' ');
            }
            line_ret.push_back('\n');
            return line_ret;
        }
        case line::ver: {
            //We'll handle both the vertical cases on a single case
            std::string emptySpace(spaces, ' ');
            size_t i = 1, j = strIn.length() - 2; // we skip the first and last characters 
                //as those should be in the bottom and up lines
            for(size_t k = 0; k < strIn.length()-2; i++, j--, k++) {
                line_ret.push_back(toupper(strIn[i]));
                line_ret += emptySpace;
                line_ret.push_back(toupper(strIn[j]));
                line_ret.push_back('\n');
            }
            return line_ret;
        }
        default: 
            //This is exceptional because someone had to specificall write static_cast<line>(somebadint)
            //or a similar cast
            throw std::invalid_argument("You fucked up the \' line l \' argument, gj");
    }
}

std::string makeBox(std::string strIn) 
{
    std::string box = makeLine(strIn, line::hor) 
                    + makeLine(strIn, line::ver, 2 * strIn.length() - 3)
                    + makeLine(strIn, line::hor_rev)
                    ;
    return box;

}
void boxify()
{
    std::cout << "Please input the string you'd like to see as a box: ";
    std::string toBox, firstLine, box;
    std::getline(std::cin, toBox);
    if(toBox.length() <= 1) { std::cout << "You can't make a box out of one character!"; }
    else { std::cout<<"Your box is:\n" << makeBox(toBox); }
}

int main()
{
    boxify();
    return 0;
}