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Author

Help with Data Structures...

Sneha Kashyap
Greenhorn

Joined: May 06, 2009
Posts: 22
Hi,

I am unable to decide as to which data structure to use for the following purpose
Slno Name
01 abc
01 def
02 abc
03 xyz

I want these to be grouped and then stored accordingly Like: 01 {abc,def}
02 {abc}
03 {xyz}
I want to group these as itemsets based on the sl no value.

Please Help Thanks in advance.
mahesh shinde
Ranch Hand

Joined: Jul 24, 2009
Posts: 69

you mean which collection class
Sneha Kashyap
Greenhorn

Joined: May 06, 2009
Posts: 22
Thanks, Yeah and how to use it to achieve the same.
Ulf Dittmer
Marshal

Joined: Mar 22, 2005
Posts: 41621
    
  55
How about Map<Integer, List<String>>?

Or maybe Map<String, List<String>> if the "01" is a string and not an integer.


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Sneha Kashyap
Greenhorn

Joined: May 06, 2009
Posts: 22
Thanks, but map cannot contain duplicate values, I need to have duplicate keys, like 01 mapping to abc,def Can you help me as to how this can be achieved.
saipraneeth nallapareddy
Ranch Hand

Joined: Dec 02, 2009
Posts: 159
i guess it is TreeSet which will eliminate the duplicate not the HashMap.
name-value pairs are sufficient.
don't confuse with HashSet and HashMap.
Ulf Dittmer
Marshal

Joined: Mar 22, 2005
Posts: 41621
    
  55
Thanks, but map cannot contain duplicate values, I need to have duplicate keys, like 01 mapping to abc,def

That's not duplicate keys in the Map, that's multiple entries in the List.
Campbell Ritchie
Sheriff

Joined: Oct 13, 2005
Posts: 38509
    
  23
Sneha Kashyap wrote: Thanks, but map cannot contain duplicate values, I need to have duplicate keys, like 01 mapping to abc,def Can you help me as to how this can be achieved.
Ulf has already told you what to do.
 
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subject: Help with Data Structures...