12. Integer to Roman

Given an integer, convert it to a roman numeral.

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

题意：整数转为罗马序列。

思路：把1000,900,500,400,100,90,50,40,10,9,5,4,1作为基数，然后进行除法和取余运算。

class Solution {public:string intToRoman(int num) {string s;int base[] = { 1000, 900, 500, 400, 100, 90, 50, 40, 10, 9, 5, 4, 1 };string roman[] = {"M", "CM", "D", "CD", "C", "XC", "L", "XL", "X", "IX", "V", "IV", "I"};int i = 0;while (num){int j = 0;j = num / base[i];num %= base[i];while (j--){s += roman[i];}i++;}return s;}};