LeetCode: Integer to Roman

这题因为不知道罗马数是怎么一回事。。就去网上找了答案

class Solution {
public:
    string intToRoman(int num) {  
      // Start typing your C/C++ solution below  
      // DO NOT write int main() function    
      char symbol[7] = {'I', 'V', 'X', 'L', 'C', 'D', 'M'};
      int scale = 1000;
      string ret;
      for (int i = 6; i >= 0; i -= 2) {
          int digit = num / scale;
          if (digit != 0) {
              if (digit <= 3) ret = ret + string(digit, symbol[i]);
              else if (digit == 4) ret = ret + symbol[i] + symbol[i+1];
              else if (digit == 5) ret = ret + symbol[i+1];
              else if (digit <= 8) ret = ret + symbol[i+1] + string(digit-5, symbol[i]);
              else if (digit == 9) ret = ret + symbol[i] + symbol[i+2];
          }
          num %= scale;
          scale /= 10;
      }
      return ret;
    }  
};

 C#

public class Solution {
    public string IntToRoman(int num) {
        char[] sym = new char[7]{'I', 'V', 'X', 'L', 'C', 'D', 'M'};
        int scale = 1000;
        string ans = "";
        for (int i = 6; i >= 0; i-=2) {
            int digit = num / scale;
            if (digit != 0) {
                if (digit <= 3) ans  = ans + new string(sym[i], digit);
                else if (digit == 4) ans = ans + sym[i] + sym[i+1];
                else if (digit == 5) ans = ans + sym[i+1];
                else if (digit <= 8) ans = ans + sym[i+1] + new string(sym[i], digit-5);
                else if (digit == 9) ans = ans + sym[i] + sym[i+2];
            }
            num %= scale;
            scale /= 10;
        }
        return ans;
    }
}