Spreadsheet Encoding
Explore how to convert spreadsheet column IDs such as A, B, and AA into their corresponding integers by treating them as base 26 numbers. Learn the algorithmic approach and implement it in Python using the ord function to map characters to numeric values accurately. Understand how to iterate through characters and apply powers of 26 to decode the column representation effectively.
We'll cover the following...
In this lesson, we will be considering how to solve the problem of implementing a function that converts a spreadsheet column ID (i.e., “A”, “B”, “C”, …, “Z”, “AA”, etc.) to the corresponding integer. For example, “A” equals 1 because it represents the first column, while “AA” equals 27 because it represents the 27th column.
We will cover how to solve this problem algorithmically, and then code a solution to this question in Python.
The key insight is to think of the column IDs as base 26 integers.
In the illustration below, you can see how we represent “314” as a base 10 number.
From the illustration above, you can easily deduce the general formula. We start from the left-most digit and multiply it with the base raised to the power of ...