LeetCode - Excel Sheet Column Number

Excel Sheet Column Number

2015.1.23 17:54

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:

　　This is a reversed version of the paired question. So do it backward.

Accepted code:

 1 // 1AC, nice and easy
 2 class Solution {
 3 public:
 4     int titleToNumber(string s) {
 5         int base = 1;
 6         int i;
 7         int len = s.length();
 8         int sum = 0;
 9         
10         for (i = 0; i < len; ++i) {
11             sum = sum * 26 + (s[i] - 'A');
12         }
13         for (i = 1; i < len; ++i) {
14             base *= 26;
15             sum += base;
16         }
17         sum += 1;
18         
19         return sum;
20     }
21 };

 

转载于:https://www.cnblogs.com/zhuli19901106/p/4244794.html