aspose file tools*
The moose likes Beginning Java and the fly likes Logic problem Big Moose Saloon
  Search | Java FAQ | Recent Topics | Flagged Topics | Hot Topics | Zero Replies
Register / Login

Win a copy of The Java EE 7 Tutorial Volume 1 or Volume 2 this week in the Java EE forum
or jQuery UI in Action in the JavaScript forum!
JavaRanch » Java Forums » Java » Beginning Java
Bookmark "Logic problem" Watch "Logic problem" New topic

Logic problem

Tarun Oohri
Ranch Hand

Joined: Feb 20, 2013
Posts: 175
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: 14114

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.

Java Beginners FAQ - JavaRanch SCJP FAQ - The Java Tutorial - Java SE 7 API documentation
Scala Notes - My blog about Scala
Campbell Ritchie

Joined: Oct 13, 2005
Posts: 38412
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: 11246

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
Ranch Hand

Joined: Oct 21, 2000
Posts: 4340

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

Visit my download page
Campbell Ritchie

Joined: Oct 13, 2005
Posts: 38412
You're welcome
It is sorta covered in the JavaRanch Style Guide.
subject: Logic problem