spell.cpp

// Spells the input using the NATO phonetic alphabet

/* Possible usage scenarios:

 spell # spells from the console, end with CTRL+D (UNIX) or CTRL+Z (Windows)
 spell "text"
 cat file | spell

*/

#include <cctype>
#include <cstdlib>
#include <iostream>
#include <unordered_map>

void spell(std::string const& str,
           std::unordered_map<char, std::string> const& dict) {
    for (auto&& elem : str) {
        std::cout << elem;
        if (dict.find(std::toupper(elem)) != dict.end()) {
            std::cout << " - " << dict.at(std::toupper(elem));
        }
        std::cout << '\n';
    }
}

int main(int argc, char** argv) {
    std::unordered_map<char, std::string> dict;
    // Convention: use capital letters for the keys
    dict['A'] = "Alpha";
    dict['B'] = "Bravo";
    dict['C'] = "Charlie";
    dict['D'] = "Delta";
    dict['E'] = "Echo";
    dict['F'] = "Foxtrot";
    dict['G'] = "Golf";
    dict['H'] = "Hotel";
    dict['I'] = "India";
    dict['J'] = "Juliet";
    dict['K'] = "Kilo";
    dict['L'] = "Lima";
    dict['M'] = "Mike";
    dict['N'] = "November";
    dict['O'] = "Oscar";
    dict['P'] = "Papa";
    dict['Q'] = "Quebec";
    dict['R'] = "Romeo";
    dict['S'] = "Sierra";
    dict['T'] = "Tango";
    dict['U'] = "Uniform";
    dict['V'] = "Victor";
    dict['W'] = "Whiskey";
    dict['X'] = "X-ray";
    dict['Y'] = "Yankee";
    dict['Z'] = "Zulu";

    if (argc > 2) {
        std::cerr << "Usage: " << argv[0] << " [text]\n";
        std::exit(EXIT_FAILURE);
    }

    std::string str;
    if (argc == 1) // spells from the standard input
    {
        while (std::getline(std::cin, str)) {
            spell(str, dict);
            std::cout << "----- newline -----\n";
        }
    } else // spells specifed text
    {
        spell(argv[1], dict);
    }
}