Excel Sheet Column Title

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

其实就是10进制转26进制， 但是要注意的是A对应的是1，而不是0， 所以每次都要先-1。要倒过来输出。

public class Solution {
public String convertToTitle(int n) {
StringBuilder sb = new StringBuilder();
while(n > 0){
sb.insert(0,(char)((n - 1) % 26 + 'A'));
n = (int)(n - 1) / 26;
}
return sb.toString();
}
}