将整数转换为罗马数字等价物

Question

鉴于此图表：

我想将整数转换成他们尊重的罗马字母。例如，假设我们有一个整数列表，如：[1, 49, 23]。该方法应该 return 像这样：['I', 'XLIX', 'XXIII']。 49 是 40 + 9 所以它将是 'XLIX'.

这是我目前在 Java 中写的内容：

public static List<String> romanizer(List<Integer> numbers) {
        String[] romanLetters = {"I", "IV", "V", "IX", "X", "XL", "L", "XC", "C", "CD", "D", "CM", "M" };
        int[] numberArray = { 1, 4, 5, 9, 10, 40, 50, 90, 100, 400, 500, 900, 1000 };
        ArrayList<String> result = new ArrayList<>();
        int times = 0;

        for (int h = numberArray.length - 1; h >= 0; h--) {
            for (int d = 0; d < numbers.size(); d++) {
                times = numbers.get(d) / numberArray[h];
                numbers.set(d, numbers.get(d) % numberArray[h]);
            }
            while (times > 0) {
                result.add(romanLetters[h]);
                times--;
            }
        }
        return result;
    }

但我却得到了这样的结果：[X, X, I, I, I]。任何人都可以 help/see 这个问题？

Answer 1

为了尽量减少混淆，我建议使用两个函数而不是一个函数：

private static final String[] ROMAN_LETTERS = {"I", "IV", "V", "IX", "X", "XL", "L", "XC", "C", "CD", "D", "CM",  "M" };
private static final int[] ROMAN_NUMBERS    = {  1,    4,   5,    9,  10,   40,  50,   90, 100,  400, 500,  900, 1000 };

public static String romanizer(int num) {
    StringBuilder result = new StringBuilder();
    for (int h = ROMAN_NUMBERS.length - 1; h >= 0; h--) {
        result.append(ROMAN_LETTERS[h].repeat(num / ROMAN_NUMBERS[h]));
        num = num % ROMAN_NUMBERS[h];
    }
    return result.toString();
}

public static List<String> romanizer(List<Integer> numbers) {
    List<String> result = new ArrayList<>();
    for (int num : numbers)
        result.add(romanizer(num));
    return result;
}

将整数转换为罗马数字等价物

Converting integers to their roman numeral equivalents

java

arrays

arraylist