### Question

Related to question Excel Sheet Column Title

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

For example:

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

**Credits:**

Special thanks to @ts for adding this problem and creating all test cases.

### Analysis

This question I’ve seen it quite a few time. It’s very standard integer conversion question.

### Solution

Please read this post **[ItInt5] Excel Decimal Conversion**.

### Code

recursively:

```
public class Solution {
public String convertToTitle(int n) {
if (n < 1) {
return "";
}
n--;
char ch = (char) ((n % 26) + 'A');
return convertToTitle(n / 26) + ch;
}
}
```