LeetCode 171 Excel Sheet Column Number

Posted 2020-08-06

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 

 

思路：

相当于26进制转10进制，要注意A从1开始而不是从0开始的边界条件。

 

解法：

public class Solution
{
    public int titleToNumber(String s)
    {
        int sum = 0;
        int temp;

        for(int i = 0; i < s.length(); i++)
        {
            temp = s.charAt(i) - ‘A‘ + 1;
            sum = sum * 26 + temp;
        }

        return sum;
    }
}