12. Integer to Roman

LeetCode
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My Solution (subtraction, Greedy)

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class Solution {
    public String intToRoman(int num) {
        StringBuilder sb = new StringBuilder();
        while(num > 0){
            if (num >= 1000){
                sb.append('M');
                num -= 1000;
            }else if (num >= 900){
                sb.append("CM");
                num -= 900;
            }else if (num >= 500){
                sb.append('D');
                num -= 500;
            }else if (num >= 400){
                sb.append("CD");
                num -= 400;
            }else if (num >= 100){
                sb.append('C');
                num -= 100;
            }else if (num >= 90){
                sb.append("XC");
                num -= 90;
            }else if (num >= 50){
                sb.append('L');
                num -= 50;
            }else if (num >= 40){
                sb.append("XL");
                num -= 40;
            }else if (num >= 10){
                sb.append('X');
                num -= 10;
            }else if (num >= 9){
                sb.append("IX");
                num -= 9;
            }else if (num >= 5){
                sb.append('V');
                num -= 5;
            }else if (num >= 4){
                sb.append("IV");
                num -= 4;
            }else{
                sb.append('I');
                num -= 1;
            }
        }
        return sb.toString();
    }
}

Clearer

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class Solution {
    public String intToRoman(int num) {
        int[] values = {1000, 900, 500, 400, 100, 90, 50, 40, 10, 9, 5, 4, 1};
        String[] symbols = {
            "M", "CM", "D", "CD", "C", "XC",
            "L", "XL", "X", "IX", "V", "IV", "I"
        };
        
        StringBuilder sb = new StringBuilder();
        for (int i = 0; i < values.length && num > 0; i++) {
            while (num >= values[i]) {
                num -= values[i];
                sb.append(symbols[i]);
            }
        }
        return sb.toString();
    }
}