數值轉大寫

兩年前有陣子上Leetcode試玩了一下。 其中有一題Integer to Roman，

沒想到兩年多了還是維持在最快(3ms， 再快真的不容易)

程式碼如下：

class Solution {
    public String intToRoman(int num) {
        int[] nums = new int[]{1000, 900, 500, 400, 100, 90, 50, 40, 10, 9, 5, 4};
        String[] rns = new String[]{"M", "CM", "D", "CD", "C", "XC", "L", "XL", "X", "IX", "V", "IV"};
        StringBuilder sb = new StringBuilder();
        int pos = 0;
        while (num > 3 && pos < rns.length) {
            int d = num / nums[pos];
            int r = num % nums[pos];
            if (d > 0) {
                for (int i = 0; i < d; i++) {
                    sb.append(rns[pos]);
                }
            } else {
                pos++;
            }
            num = r;
        }
        while (num-- > 0) {
            sb.append('I');
        }
        return sb.toString();
 
    }
}

不過這對於我們用中文的來說，比較實用的還是轉國字大寫

	import java.util.regex.Pattern;
	/**
	* @author Kent Yeh
	*/
	public class ZhBigNum {
	public static final Pattern ZEROP = Pattern.compile("\\x{96F6}{2,}");
	public static void main(String[] args) {
	System.out.println(toZhBigNum("1002000304050"));
	System.out.println(toZhBigNum("305000"));
	System.out.println(toZhBigNum("100020003000"));
	}
	public static String toZhBigNum(String value) {
	char[] bd = new char[]{'零', '壹', '貳', '參', '肆', '伍', '陸', '柒', '捌', '玖'};
	String[] tail1 = new String[]{"", "拾", "佰", "仟"};
	String[] tail2 = new String[]{"", "萬", "億", "兆"};
	StringBuilder res = new StringBuilder();
	int pos = 0;
	boolean fnz = false;//每4個一組，直到碰到不是0才為true
	for (char c : new StringBuilder(value).reverse().toString().toCharArray()) {
	int d = c;
	int r = pos / 4;
	int m = pos % 4;
	boolean nz = c > 48;
	fnz = m == 0 ? c > 48 : c > 48 || fnz;
	res.append(nz ? tail2[r] : "").append(nz ? tail1[m] : "").append(fnz ? bd[d - 48] : "");
	if (nz) {
	tail2[r] = "";
	}
	pos++;
	}
	return ZEROP.matcher(res.reverse().toString()).replaceAll("零");
	}
	public static String toZhBigNumFast(String value) {
	char[] bd = new char[]{'零', '壹', '貳', '參', '肆', '伍', '陸', '柒', '捌', '玖'};
	String[] tail1 = new String[]{"", "拾", "佰", "仟"};
	String[] tail2 = new String[]{"", "萬", "億", "兆"};
	StringBuilder res = new StringBuilder();
	boolean fnz = false;//每4個一組，直到碰到不是0才為true
	char[] cs = value.toCharArray();
	int len = cs.length;
	for (int i = len - 1; i > -1; i--) {
	int d = cs[i];
	int pos = len - i - 1;
	int r = pos / 4;
	int m = pos % 4;
	boolean nz = d > 48;
	fnz = m == 0 ? d > 48 : d > 48 || fnz;
	res.append(nz ? tail2[r] : "").append(nz ? tail1[m] : "").append(fnz ? bd[d - 48] : "");
	if (nz) {
	tail2[r] = "";
	}
	}
	return ZEROP.matcher(res.reverse().toString()).replaceAll("零");
	}
	}

view raw ZhBigNum.java hosted with ❤ by GitHub

	function reverseString(str) {
	return str.split('').reverse().join('');
	}
	function toZhBigNum(snum){
	if(!snum||snum===0||snum==='零')
	return '零';
	snum = ''+snum;
	let bd = ['零', '壹', '貳', '參', '肆', '伍', '陸', '柒', '捌', '玖'];
	let tail1=['', '拾', '佰', '仟'];
	let tail2=['', '萬', '億', '兆'];
	let fnz = false;
	let len = snum.length;
	let res = '';
	for (let i = len - 1; i > -1; i--) {
	let d = snum.charCodeAt(i);
	let pos = len - i - 1;
	let r = Math.floor(pos / 4);
	let m = pos % 4;
	let nz = d > 48;
	fnz = m == 0 ? d > 48 : d > 48 || fnz;
	if(nz)
	res = res + tail2[r] + tail1[m];
	if(fnz){
	res = res + bd[d - 48];
	}
	if(nz)
	tail2[r] = '';
	}
	return reverseString(res).replace(/\u96F6{2,}/g, '零');
	}

view raw ZhBigNum.js hosted with ❤ by GitHub