Last Updated: 25 Jul, 2020
Excel Column Number
Easy
Asked in companies
You have been given a column title as appears in an Excel sheet, return its corresponding column number.
For example:
A -> 1
B -> 2
C -> 3
...
Z -> 26
AA -> 27
AB -> 28
...
Input Format
The only line of input contains a string S i.e. column title
Constraints:
1 <= |S| <= 10
Input contains only uppercase English Alphabet letters
Time Limit : 1 sec
Output Format
The only line of output will print the column number corresponding to given column title
Approaches
The process is very much similar to binary to decimal conversion. In this case, the base of the given system is to be taken as 26. Also, in this system 1 is represented as ‘A’, 2 is represented as ‘B’ and so on till 26 is represented as ‘Z’
For example-
CDA can be converted as 3*26*26 + 4*26 + 1
= 26(3*26 + 4) + 1
= 26(0*26 + 3*26 + 4) + 1
AB can be converted as 1*26 + 2