[leetCode]168. Excel Sheet Column Title

题目描述

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

解题思路

这题类比26进制，不同之处在于1-26而非0-25，所以每次求余之前先减一。

java代码

public String convertToTitle(int n) {
StringBuilder s = new StringBuilder();
while (n > 0){
s = s.append((char)(((n - 1) % 26) + 'A'));
n = (n - 1) / 26;
}
return s.reverse().toString();
}