Given a positive integer, return its corresponding column title as appear in an Excel sheet.

For example:

    1 -> A
    2 -> B
    3 -> C
    ...
    26 -> Z
    27 -> AA
    28 -> AB 


26进制的实现。

没什么难点。就是需要需要注意是 n = (n-1)/26

 

public class Solution {
    public String convertToTitle(int n) {
        if (n == 0){
            return "";
        }
        StringBuffer str = new StringBuffer();
        while (n != 0){
            int pos = (n - 1) % 26;
            char ch = (char) ('A' + pos);
            str.insert(0, ch);
            n = (n - 1) / 26;
        }
        return str.toString();
    }
}