To understand what yield does, you must understand what generators are. And before you can understand generators, you must understand iterables. Iterables When you create a list, you can read its items one by one. Reading its items one by one is called iteration: >>> mylist = [1, 2, 3] >>> for i in mylist: … Read more
You can use Enhanced for loop to iterate over a vector for (Integer digit : digits) { } We also know the size of the vector, we can write a for loop using vector.size(). for(int index = 0; index < digits.size(); index++) { System.out.println(digits.get(index)); } You can also follow the other ways given here 1 … Read more
You probably want this: ifstream inFile1(“file1.txt”),inFile2(“file2.txt”); istream_iterator<double> start(inFile1), end; there is nois thing in your code, so you get your error 1 solved error: ‘is’ was not declared in this scope
Not only the commented line, but another will also fail if there is space in the begin of string. First line fail (to compile) because string::find_first_not_of return size_t. And construct string from two size just make no sense. Second line may fail because string::substr accept length (not end) as it’s second parameter. 1 solved c++ … Read more
You are having a method named getSpellEffect() inside the main() method. You cannot have methods inside methods. Check Methods inside methods import java.util.ArrayList; import java.util.Iterator; import java.util.List; public class SpellsList { static List<Spell> spellsList = new ArrayList<Spell>(); static { spellsList.add(new Spell(“Fireball”, “damage”, 5)); spellsList.add(new Spell(“Ice Storm”, “damage”, 8)); spellsList.add(new Spell(“Heal”, “heal”, 8)); } static String … Read more
You don’t have to use auto if you don’t want to, but you can of course. The type returned by std::vector<int>::begin() and std::vector<int>::end() is a std:vector<int>::iterator (or std:vector<int>::const_iterator, depending on context), it is not an int. You could as well have written this instead: for(vector<int>::iterator it=vect1.begin(); it<vect1.end();it++){ cout<<*it<<endl; } or for(vector<int>::const_iterator it=vect1.begin(); it<vect1.end();it++){ cout<<*it<<endl; } … Read more
From the error message you provided it looks like you need to change the arguments of your operator == function from Myclass & to const Myclass &. solved C++ Constructor and vector, iterator
According to java doc, Map.keyset() Returns a set view of the keys contained in this map. The set is backed by the map, so changes to the map are reflected in the set, and vice-versa. If the map is modified while an iteration over the set is in progress (except through the iterator’s own remove … Read more
The find member function of std::map specializations returns a past-the-end iterator if the key does not exist. So you need to compare to the container’s end(): auto f = cnt.find(“asdasd”); if (f != cnt.end()) { std::cout << f->second; } solved Program crashes on trying to access the key that does not exist in map [duplicate]
You got that exception because the class String has no instance method each: String.instance_methods.include?(:each) #=> false If packages is a string need to operate on an array comprised of that string alone. We can use the method Kernel#Array to write: Array(packages).each do |package| Array(packages) will return packages if packages is an array and will return … Read more
When you execute these lines: vector<string> wordSets(24); wordSets.push_back(“CHICKEN”); wordSets has 24 empty items an the item “CHICKEN”. I suspect, you didn’t mean that. Changing the first line to: vector<string> wordSets; should fix the wrong number of items problem. If you want to reduce the number of times memory is allocated by calls to push_back, you … Read more
The two are not equivalent. The semantics of how execution is deferred between the two Bar methods is different. Foo.Bar will evaluate Sequence into an IEnumerable value when you call Bar. Foo2.Bar2 will evaluate Sequence into the value in that variable when you enumerate the sequence returned by Bar2. We can write a simple enough … Read more
Your function takes 2 iterables and counts the number of times, by index, the number from one iterable is greater than the other. It then does the same operation with lists in the opposite order. It’s far easier to show an example: def solve(a, b): return map(lambda t: sum([x > y for x, y in … Read more
How about this? ArrayList<HashMap<String, HashMap<String, String>>> list = new ArrayList<>(); for (HashMap<String, HashMap<String, String>> m : list) { for (Map.Entry<String, HashMap<String, String>> e : m.entrySet()) { String key1 = e.getKey(); for (Map.Entry<String, String> me : e.getValue().entrySet()) { String key2 = me.getKey(); String value = me.getValue(); } } } Note that you really should be using … Read more
In an unordered_set, the order of inserts does not necessarily correspond to the order that you will get when the set is iterated (hence the name “unordered”). Part of the reason why a bi-directional iterator is not supported(using a — operator) in this data structure is because being able to go backwards/forwards on an unordered_set … Read more