Incorrect arithmetic answers

[Saksham Saxena]

Hello,

I was trying to implement Substring Search using a rolling hash function (fairly simple implementation): https://play.golang.org/p/_fjgxPC06So

This works correctly and as expected. However, if you change the const `baseNumber` to 128, the program is unable to do the intermediate arithmetic incorrectly (see the difference after running it). 

How could this be ? I've stared at it long enough and it doesn't seem like it's overflowing (or is it really ? I thought float64 had great range ?)

Any ideas/comments are appreciated. 

Thanks!

Saksham

[crate...@gmail.com]

Floating point calculations are imprecise.

https://0.30000000000000004.com/

https://www.phys.uconn.edu/~rozman/Courses/P2200_15F/downloads/floating-point-guide-2015-10-15.pdf

s

[Michael Jones]

fixed, in light of the prior crucial comment...

https://play.golang.org/p/d-AwGEwj_YB

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Michael T. Jones
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