leetcode解题: Integer to Roman (12)

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Given an integer, convert it to a roman numeral.

Input is guaranteed to be within the range from 1 to 3999.

解法1：

主要的思路是要先构造出来罗马数字中的“根”数。也就是说，除了那么1,5,10,50,100,500,1000的数字，还有那些需要特殊处理的，比如40.
然后得算法就简单了，就遍历一遍dict， 每当找出来一个比当前base小的数就计算出需要重复几遍，比如III。
然后更新base数值。
Java

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public class Solution {
    public String intToRoman(int n) {
        // Write your code here
        
         
        String dict[] = new String[]{"M", "CM", "D", "CD", "C", "XC", "L", "XL", "X", "IX", "V", "IV", "I"};
        int base[] = new int[]{1000, 900, 500, 400, 100, 90, 50, 40, 10, 9, 5, 4, 1};
        
        String res = "";
        for (int i = 0; i < dict.length; i++) {
            if (n >= base[i]) {
                
                int count = n / base[i];
                n = n % base[i];
                for (int j = 0; j < count; j++) {
                    res += dict[i];
                }
            }
        }
        
        return res;
        
    }
}