1.描述

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

2.分析

3.代碼

int titleToNumber(char* s) {
    if (NULL == s) return 0;
    int colnum = 0;
    unsigned int length = strlen(s);
    for (unsigned int i = 0 ;i < length; ++i) {
        colnum = colnum * 26 + s[i] - 'A' + 1;
    }
    return colnum;
}