12. Integer to Roman

Description:

iven an integer, convert it to a roman numeral.

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

思路：题目还是算简单的吧，规定了1到3999的范围，我直接利用了贪心算法，每次都取最大的那个数，组合起来就解决了问题

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