171 Excel Sheet Column Number – Easy
Problem:
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
Thoughts:
This is like a base of 26 system problem. It’s similar but easier than the reverse.
Because no need to worry about minus one problem.
Solutions:
public class Solution {
public int titleToNumber(String s) {
int result = 0;
for (int i = 0; i < s.length(); i ++) {
int digit = s.charAt(i) - 'A' + 1;
result = result * 26 + digit;
}
return result;
}
}