Integer_to_Roman.cpp

// http://oj.leetcode.com/problems/integer-to-roman/
// Time Complexity: O(n), Space Complexity: O(1)
class Solution {
public:
	string intToRoman(int num) {
		const int radix[] = {1000, 900, 500, 400, 100, 90,
		50, 40, 10, 9, 5, 4, 1};
		const string symbol[] = {"M", "CM", "D", "CD", "C", "XC",
		"L", "XL", "X", "IX", "V", "IV", "I"};
		string roman;
		for (size_t i = 0; num > 0; ++i) 
		{
			int count = num / radix[i];
			num %= radix[i];
			for (; count > 0; --count) roman += symbol[i];
		}
		return roman;
	}
};