/*

Author: King, wangjingui@outlook.com

Date: Dec 28, 2014

Problem: Excel Sheet Column Number

Difficulty: Medium

Source: https://oj.leetcode.com/problems/excel-sheet-column-number/

Notes:

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

Solution: 1. ...

*/

public class Solution {

public int titleToNumber(String s) {

int res = 0;

if (s.length() == 0) return 0;

for (int i = 0; i < s.length(); ++i) {

res = res * 26 + s.charAt(i) - 'A' + 1;

}

return res;

}

}