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Logic problem

Tarun Oohri
Ranch Hand

Joined: Feb 20, 2013
Posts: 166
Hi everyone
I am not able to understand this program, It counts the repeated characters in the given string.
Can you tell me how it is doing so, what is the logic behind this.
What 65,91,97,123 denotes here ?
Thanks in advance!!!
Jesper de Jong
Java Cowboy
Saloon Keeper

Joined: Aug 16, 2005
Posts: 13868

Those numbers are character codes (ASCII). It only counts characters in the range 65 to 91 and 97 to 123 (inclusive), which are letters A to Z and a to z, and the characters [ and {. The fact that it includes [ and { is probably a bug. It should have been < 91 and < 123.

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Campbell Ritchie

Joined: Oct 13, 2005
Posts: 36453
Where did you find that code? It would have been far better to use a method like this than those error‑prone <= operators.
fred rosenberger
lowercase baba

Joined: Oct 02, 2003
Posts: 10906

those are what's called "magic numbers", because you have to have some magic to know what they mean. They should be avoided at all cost.

There are only two hard things in computer science: cache invalidation, naming things, and off-by-one errors
Randall Twede
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Joined: Oct 21, 2000
Posts: 4339

awesome Campbell! thanks for sharing that for when i might need it!

Visit my download page
Campbell Ritchie

Joined: Oct 13, 2005
Posts: 36453
You're welcome
I agree. Here's the link:
subject: Logic problem
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