Excel Column Number Conversion

Given a column title as it appears in an Excel sheet, your task is to return its corresponding column number.

Example:

Input:

S = "AB"

Output:

28

Explanation:

The sequence is as follows:
A - 1
B - 2
C - 3
...
Z - 26
AA - 27
AB - 28

Constraints:

1

Question

Given a column title as it appears in an Excel sheet, your task is to return its corresponding column number.

S = "AB"

The sequence is as follows:
A -> 1
B -> 2
C -> 3
...
Z -> 26
AA -> 27
AB -> 28

Consider implementing the function to convert the Excel column title to a number. You do not have to handle input/output explicitly.

Accepted Answer

Convert Excel column title to corresponding column number.

Iterate through the characters in the input string from right to left
Calculate the corresponding value of each character based on its position and multiply by 26^index
Sum up all the values to get the final column number

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