duplicates

I have the following setup: public class A { private Set<C> cSet; } public class B { private Set<C> cSet; } public class C {} A's and B's cSet might have references to same C instances. I want to serialize A and B such that upon deserialization I don't have duplicate C objects. Will Java know how to do the right thing if I serialize/deserialize it into the same ObjectOutputStream, or might I end up with more C instances than I started out with? No, you won't get more instances of C than necessary. That's because internally, the ObjectOutputStream registers every ever serialized object in a

I'm stuck figuring this out and wonder if anyone could point me in the right direction... From this list: N = [1,2,2,3,3,3,4,4,4,4,5,5,5,5,5] I'm trying to create: L = [[1],[2,2],[3,3,3],[4,4,4,4],[5,5,5,5,5]] Any value which is found to be the same is grouped into it's own sublist. Here is my attempt so far, I'm thinking I should use a while loop? global n n = [1,2,2,3,3,3,4,4,4,4,5,5,5,5,5] #Sorted list l = [] #Empty list to append values to def compare(val): """ This function receives index values from the n list (n[0] etc) """ global valin valin = val global count count = 0 for i in xrange

i have an array which might contain duplicate elements(more than two duplicates of an element). I wonder if it's possible to find and remove the duplicates in the array: without using Hash Table (strict requirement) without using a temporary secondary array. No restrictions on complexity. P.S : This is not Home work question Was asked to my friend in yahoo technical interview Sort the source array. Find consecutive elements that are equal. (I.e. what std::unique does in C++ land). Total complexity is N lg N, or merely N if the input is already sorted. To remove duplicates, you can copy

Here is the error message I receive when compiling ... Ld /Users/ilia3546/Library/Developer/Xcode/DerivedData/MasterDetail-fhgogwnbpzovbtaskgecptdnvgjs/Build/Products/Debug-iphonesimulator/MasterDetail.app/MasterDetail normal i386 cd /Users/ilia3546/Проекты/iDecide setenv IPHONEOS_DEPLOYMENT_TARGET 5.0 setenv PATH "/Applications/Xcode.app/Contents/Developer/Platforms/iPhoneSimulator.platform/Developer/usr/bin:/Applications/Xcode.app/Contents/Developer/usr/bin:/usr/bin:/bin:/usr/sbin:/sbin" /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/clang -arch i386

I have Pojo object, with getAsJson function to return Json string for this object. I use JsonProperty to define json properties in this object. Use writeValueAsString of ObjectMapper to write json string for this object. import org.codehaus.jackson.JsonGenerationException; import org.codehaus.jackson.annotate.JsonIgnore; import org.codehaus.jackson.annotate.JsonIgnoreProperties; import org.codehaus.jackson.annotate.JsonProperty; import org.codehaus.jackson.map.JsonMappingException; import org.codehaus.jackson.map.ObjectMapper; @JsonIgnoreProperties(ignoreUnknown=true) public class

How could I merge two hashes that results in no new keys, meaning the merge would merge keys that exist in both hashes? For example, I want the following: h = {:foo => "bar"} j = {:foo => "baz", :extra => "value"} puts h.merge(j) # {:foo => "baz"} I'm looking for a really clean way of doing this as my current implementation is pretty messy. You could remove keys that weren't in the first hash from the second hash, then merge: h.merge j.select { |k| h.keys.include? k } Unlike my edited-out alternative, this is safe if you decide to change it to a merge! or update . Yjerem's answer works in Ruby

I have a table that has a lot of duplicates in the Name column. I'd like to only keep one row for each. The following lists the duplicates, but I don't know how to delete the duplicates and just keep one: SELECT name FROM members GROUP BY name HAVING COUNT(*) > 1; Thank you. Roee Adler See the following question: Deleting duplicate rows from a table . The adapted accepted answer from there (which is my answer, so no "theft" here...): You can do it in a simple way assuming you have a unique ID field: you can delete all records that are the same except for the ID, but don't have "the minimum ID"

I have a table of baseball players(all 1000 or so), with fields: mysql> describe person; +-----------+-------------+------+-----+---------+----------------+ | Field | Type | Null | Key | Default | Extra | +-----------+-------------+------+-----+---------+----------------+ | id | int(11) | NO | PRI | NULL | auto_increment | | firstname | varchar(30) | NO | | NULL | | | lastname | varchar(30) | NO | | NULL | | +-----------+-------------+------+-----+---------+----------------+ But I think there are some players that have gotten added in twice. How can I go through and check for how many