edaBit-coding-challenges/Roman-Numeral-Converter/code.cpp

/*  Create a function that takes an Arabic number and converts 
 *  it into a Roman number.
 *  All roman numerals should be returned as uppercase.
 *  The largest number that can be represented in this notation is 3,999.
 */
//  1 = I, 4 = IV, 5 = V, 6 = VI, 9 = IX, 
//  10 = X, 50 = L , 100 = C , 500 = D , 1000 = M 
std::string convertToRoman(int num) {
	//  array of int corresponding to roman numeral values 
	int val[13] = {1,4,5,9,10,40,50,90,100,400,500,900,1000};
	std::vector<std::string> roman = {"I","IV","V","IX","X","XL",
												"L","XC","C","CD","D","CM","M"};
	std::string r = "";
	int i = roman.size()-1;
	  //  starting with the biggest number, populate "r" with equivalent roman numeral  
	while(num>0){
		//  how many times to add the current letter(s) 
		int fixIt = num/val[i];
		//  add the current leter(s) to the string
		while(fixIt--){
			r += roman[i];
		}
		//  replace the previous value of num with remainder
		num = num%val[i];
		i--;
	}
	return r;
}