[LeetCode]Excel Sheet Column Title

这个题挺有意思的，要注意是从1开始的

public class Solution {
    public String convertToTitle(int n) {
        String result = "";
        while (n > 0) {
            n = n - 1;
            int tmp = n % 26;
            result = (char)('A' + tmp) + result;
            n = n / 26;
        }
        return result;
    }
}