171.Excel-Sheet-Column-Number

171. Excel Sheet Column Number

题目地址

题目描述

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
...
Example 1:
​
Input: "A"
Output: 1
Example 2:
​
Input: "AB"
Output: 28
Example 3:
​
Input: "ZY"
Output: 701

代码

Approach #1

class Solution {
public int titleToNumber(String s) {
int result = 0;
for(int i = 0 ; i < s.length(); i++) {
result = result * 26 + (s.charAt(i) - 'A' + 1);
}
return result;
}
}