October 2025
Intermediate to advanced
100 pages
2h 27m
English
Content preview from Kotlin Brain TeasersBecome an O’Reilly member and get unlimited access to this title plus top books and audiobooks from O’Reilly and nearly 200 top publishers, thousands of courses curated by job role, 150+ live events each month,
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Discussion
Why does adding one to 16,777,217 seem to make the number smaller?
You probably spotted the letters L and f next to the numbers in the code. They don’t change the numerical values we’re dealing with, but they do change the way those numbers are stored in memory—L is for Long, and f is for Float.
To add a Float to a Long, Kotlin converts both values to the Float type. With only a limited number of significant figures, a Float can’t store the exact value for a number of this magnitude, and the operation ends up being performed with imprecise rounded values.
Significant Bits
The choice to use a Long instead of an Int here is just to demonstrate the L suffix and doesn’t change the outcome of the puzzle. 16,777,217 is well within the range ...
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I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.