multimap

问题 First part of the question is that I am trying to use boost::bimap, but from the documentation it is unclear to me how to define a bidirectional multimap. The second part of the question is that I need it to be a map in one direction and a multimap in the other direction, can this be done using boost::bimap ? Has anyone experience of this or can point me to the correct page ? 回答1: All is in documentation... http://www.boost.org/doc/libs/1_51_0/libs/bimap/doc/html/boost_bimap/the_tutorial

问题 This question already has answers here : Iterating through a Collection, avoiding ConcurrentModificationException when removing objects in a loop (24 answers) Why is a ConcurrentModificationException thrown and how to debug it (7 answers) Closed 10 months ago . I don't understand why I get a ConcurrentModificationException when I iterate through this multimap . I read the following entry, but I am not sure if I understood the whole thing. I tried to add a synchronized block. But my doubt is

问题 This question already has answers here : Iterating through a Collection, avoiding ConcurrentModificationException when removing objects in a loop (24 answers) Why is a ConcurrentModificationException thrown and how to debug it (7 answers) Closed 10 months ago . I don't understand why I get a ConcurrentModificationException when I iterate through this multimap . I read the following entry, but I am not sure if I understood the whole thing. I tried to add a synchronized block. But my doubt is

问题 I have a need to add a key to a Guava Multimap with an empty collection as the value. How do I accomplish this? I tried this: map.put( "my key", null ); but calling get() returns a list with one element, which is null. I worked around this by doing the following: map.putAll("my key2", new ArrayList()) but I'm wondering if this is a bad thing to do? I know Guava automatically removes a key when the last value is removed to keep containsKey() consistent. What's my best option here? 回答1:

问题 I have a need to add a key to a Guava Multimap with an empty collection as the value. How do I accomplish this? I tried this: map.put( "my key", null ); but calling get() returns a list with one element, which is null. I worked around this by doing the following: map.putAll("my key2", new ArrayList()) but I'm wondering if this is a bad thing to do? I know Guava automatically removes a key when the last value is removed to keep containsKey() consistent. What's my best option here? 回答1:

问题 Is it possible to have multiple values for the same key in a hash table? If not, can you suggest any such class or interface which could be used? 回答1: No. That's kind of the idea of hash tables. However, you could either roll your own with a Map<YourKeyObject, List<YourValueObject>> and some utility methods for creating the list if it's not present, or use something like the Multimap from Google Collections. Example: String key = "hello"; Multimap<String, Integer> myMap = HashMultimap.create(

问题 I have two multimaps as below : ListMultimap<String, String> source_multimap = ArrayListMultimap.create(); ListMultimap<String, String> target_multimap = ArrayListMultimap.create(); for (SwiftTagListBlock s : source_tagListBlock) { Iterator<Tag> sourcetag_iterator = s.tagIterator(); while (sourcetag_iterator.hasNext()) { Tag tag = (Tag) sourcetag_iterator.next(); source_multimap.put(tag.getName(), tag.getValue()); } } for (SwiftTagListBlock t : target_tagListBlock) { Iterator<Tag> targettag

问题 Details: I have a multimap implementation that represents the adjacency list for the subset of a graph. I need to find a path through this subset of the graph, which is actually all the possible paths from a start node F to an end node G , acquired by running a breadth first search on the full graph. Implementation Ideas: The BFS quits once G is found, so you end up with G only in the values of the multimap. My idea is that if you start at the value G , get G 's "key" (let's call it H ), if H

问题 It's difficult to tell what is being asked here. This question is ambiguous, vague, incomplete, overly broad, or rhetorical and cannot be reasonably answered in its current form. For help clarifying this question so that it can be reopened, visit the help center. Closed 9 years ago . I am trying to adapt a digital electronics problem to a C++ STL based program. Originally I have 4 inputs C1, C2, C3, C4. This means I have a total of 16 combinations: 0000 0001 . . . 1111 I have a multimap

问题 why does Guava doesn't have the following factory call to create a MultiMap from a normal Map? public static <K,V> MultiMap<K,V> invertMap(Map<V,K> map); I have program-names mapped to an integer of how often they were called. I'd like to invert this, so that i can ultimately construct a TreeMap, sorted by call-count, which then are the keys leading to one or multiple program-names. 回答1: How about: public static <K,V> Multimap<K,V> invertMap(Map<V,K> map) { return Multimaps.invertFrom