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Help with Data Structures...  RSS feed

 
Greenhorn
Posts: 22
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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.
 
Ranch Hand
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you mean which collection class
 
Sneha Kashyap
Greenhorn
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Thanks, Yeah and how to use it to achieve the same.
 
Rancher
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How about Map<Integer, List<String>>?

Or maybe Map<String, List<String>> if the "01" is a string and not an integer.
 
Sneha Kashyap
Greenhorn
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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.
 
Ranch Hand
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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
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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.
 
Marshal
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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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