1027 Colors in Mars （20 分）

People in Mars represent the colors in their computers in a similar way as the Earth people. That is, a color is represented by a 6-digit number, where the first 2 digits are for Red, the middle 2 digits for Green, and the last 2 digits for Blue. The only difference is that they use radix 13 (0-9 and A-C) instead of 16. Now given a color in three decimal numbers (each between 0 and 168), you are supposed to output their Mars RGB values.

Input Specification: Each input file contains one test case which occupies a line containing the three decimal color values.

Output Specification: For each test case you should output the Mars RGB value in the following format: first output #, then followed by a 6-digit number where all the English characters must be upper-cased. If a single color is only 1-digit long, you must print a 0 to its left.

Sample Input:

15 43 71

Sample Output:

#123456

解析

就是十進位制轉13進位制

#include<iostream>
#include<string>
const char map[] = { '0','1','2','3','4','5','6','7','8','9','A','B','C' };
using namespace std;
string dec213(int num) {
	string result ;
	do {
		result += num % 13;
		num /= 13;
	} while
 
 (num != 0);
	return result;
}
int main()
{
	int N;
	cout << "#";
	for (int i = 0; i < 3; i++) {
		cin >> N;
		string result = dec213(N);
		if (result.size() == 1)
			cout << "0" << map[result[0]];
		else
			cout << map[result[1]] << map[result[0]];
	}
}