[leetcode] problem 168 – 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 
...

Example

No.1

Input: 1

Output: “A”

No.2

Input: 28

Output: “AB”

No.3

Input: 701

Output: “ZY”

Code

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public String (int n) {
StringBuilder sb = new StringBuilder();

while (n > 0) {
sb.append((char) (--n % 26 + 'A'));
n /= 26;
}

return sb.reverse().toString();
}