map

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

问题 As known the following code is used to iterate map in C++ for (std::map<char,int>::iterator it=mymap.begin(); it!=mymap.end(); ++it) { std::cout << itr->first << " => " << itr->second << '\n'; } Where itr is declared as std::map::iterator . The members first and second are declared neither in std::map nor in std::iterator. Then how is it available for access? 回答1: The elements of an std::map are std::pair<key_type, mapped_type> , so de-referencing a map iterator gives you a reference to one

问题 After updating to Chrome 29 I have noticed that the browser try to get jquery.min.map from app root. But request before it was received from assets (small reputation don't let me post screen image for proofing). Of course, I can switch off source maps in browser settings as at this question, but maybe there's another true way? And the difference in my case is that the source map was received from assets. 回答1: Source maps are only loaded by Chrome when the developer tools are opened, so it

问题 Is there a version of either java.beans.PropertyChangeSupport or com.jgoodies.binding.beans.ExtendedPropertyChangeSupport which is helpful for supporting change listeners along the lines of a Map or EnumMap? (a key-value store with known limited keys and change listeners for all the values in the map) I don't really need beans-type access, I have a number of different statistics sort of like: interface hasName() { public String getName(); } enum StatisticType implements hasName { MILES_DRIVEN

问题 void example(const map<string, vector<int> > & num); int main() { map<string, vector<int> >num; num["A"].push_back(1); example(num); return 0; } void example(const map<string, vector<int> > & num) { cout << num["A"].size() << endl; } i think the size() did not change the value of num, but why it cause error when complie it? it's ok when i removed the keyword const in the example function. 回答1: The problem isn't the call to size() . The problem is using operator[]() on a const map: if the key

问题 void example(const map<string, vector<int> > & num); int main() { map<string, vector<int> >num; num["A"].push_back(1); example(num); return 0; } void example(const map<string, vector<int> > & num) { cout << num["A"].size() << endl; } i think the size() did not change the value of num, but why it cause error when complie it? it's ok when i removed the keyword const in the example function. 回答1: The problem isn't the call to size() . The problem is using operator[]() on a const map: if the key

问题 I am searching for a library that can work similar to google maps (navigation / zooming) where I could load my own maps. Lower capabilities may also be acceptable. My maps are acceptable by Magellan Explorist GPS. I found mAppWidget: but does not provide GPS support so far. And I am not really sure if I can load my map (online or offline) in OpenStreetMaps. Thanks in advance. 回答1: You can use Osmdroid Osmdroid Home Page - specifically the jar file. You can use Mobile Atlas Creator to prepare

问题 I'm writing a translator program that reads the translations from a text file. This method reads from the text file and adds it to a Map object that i'm using for the dictionary. public Map<String, String> loadTranslations() throws IOException { Map<String, String> translations = new HashMap<String, String>(); BufferedReader in = null; try { in = new BufferedReader(new FileReader(System.getProperty("user.dir") + "\\resource\\translations.txt")); englWord = in.readLine(); frenWord = in

问题 iOS 6 MKMapView seems to be using the tons of memory, when we starts zooming and playing around with the Map View in our application(for around 7-10 mins), When we come out of the controller which has MKMapView, its some how not releasing the total memory(I am using ARC in my App). I am allocating and initializing the MKMapView thru NIB. Controller 1 -->Controller 2 (has MKMapView) 1.5MB -->40-60MB (I have used the Instruments to find out leaks, but of no use) When i come back to Controller1

问题 One of the no-nos in drools includes manually iterating over collections in the consequence (then clause). I need to write a drool which is effectively iterating over a map while doing something for each key value pair in that map. In other words, I need to duplicate the behavior of a for-each loop in drools without actually writing a for-each loop. Now, I realize I could just write a for-each loop in the consequence. I want to keep my code as close to drools-standard as possible. I have