set

问题 I have used find_if before with lists and vectors in C++ and it has worked fine. But now, when I try to use it with sets I get the following error: error: no matching function for call to ‘find_if(std::set<A, Acmp>::iterator, std::set<A, Acmp>::iterator, <unresolved overloaded function type>)’| My class is the following: bool searchForA(A i) { return (i.getVal() > 0); } void B::findA() { set<A, Acmp> cont; set<A, Acmp>::iterator it; A *a1 = new A(5); A *a2 = new A(7); cont.insert(*a1); cont

问题 I am parsing two big files (Gb size order), that each contains keys and corresponding values . Some keys are shared between the two files, but with differing corresponding values . For each of the files, I want to write to a new file the keys* and corresponding values , with keys* representing keys present both in file1 and file2. I don't care on the key order in the output, but the should absolutely be in the same order in the two files. File 1: key1 value1-1 key2 value1-2 key3 value1-3

问题 I have two classes, in class Player i have the variable which is defined as private int collectedDots and I want to access in another class Exit . I have defined the Get and Set method within class Player as such: public void setCollectedDots(int cd) { collectedDots = cd; } public int getCollectedDots() { return collectedDots; } But now I want to access the collectedDots field from the Exit class. When I copy those two methods into the Exit class I keep getting the error cannot find symbol -

问题 Trying to learn Python I encountered the following: >>> set('spam') - set('ham') set(['p', 's']) Why is it set(['p', 's']) - i mean: why is 'h' missing? 回答1: The - operator on python sets is mapped to the difference method, which is defined as the members of set A which are not members of set B . So in this case, the members of "spam" which are not in "ham" are "s" and "p" . Notice that this method is not commutative (that is, a - b == b - a is not always true). You may be looking for the

问题 This is likely very simple. I have added an std::set<int> my_set; to my header file for some class. Then, in that classes implementation, I try to insert into this set. As an example, just doing my_set.insert(1); This is not compiling, which is very strange behaviour. Here is my compiler error: error C2663: 'std::_Tree<_Traits>::insert' : 4 overloads have no legal conversion for 'this' pointer The file I included to use set is #include <set> . What have I done wrong? I have not called the set

问题 Will this fail or better way of scripting/coding the following? (particularly focusing on the first part of the script) Should I be using ELSE statements etc.? Any recommendations would be greatly appreciated! echo Setting Static IP Information... IF %POSID%==11 set IP_Addr=10.102.%DROPZERO%.105 IF %POSID%==12 set IP_Addr=10.102.%DROPZERO%.106 IF %POSID%==13 set IP_Addr=10.102.%DROPZERO%.107 IF %POSID%==14 set IP_Addr=10.102.%DROPZERO%.108 IF %POSID%==15 set IP_Addr=10.102.%DROPZERO%.109 IF

问题 I've been using this code successfully however, looking to adjust it and use when performing netsh commands to rename NIC's - although whilst writing this i'm not sure it's the best route anymore. SET _OSVer=OTHER FOR /F "Tokens=2 Delims=[]" %%a IN ('VER') DO SET _VerNo=%%a FOR /F "Tokens=2-3 Delims=. " %%b IN ("%_VerNo%") DO ( IF "%%b.%%c" EQU "5.2" SET _OSVer=2003 IF "%%b.%%c" EQU "6.0" SET _OSVer=2008 IF "%%b.%%c" EQU "6.1" SET _OSVer=2008R2 IF "%%b.%%c" EQU "6.2" SET _OSVer=2012 IF "%%b.%

问题 I have this code which associates one table to another. Using Set it collects all data and only shows it once if there are other similar values. genre_names = Set.new <% @pm_relationships = PmRelationship.where(:people_id => @person.id) %> <% @pm_relationships.each do |pm_relationship| %> <% @movie=Movie.find(pm_relationship.movie_id) %> <% @mg_relationships = MgRelationship.where(:movie_id => @movie.id) %> <% @mg_relationships.each do |mg_relationship| %> <% @genre=Genre.find(mg_relationship

问题 I'm trying to build a channel with reliable delivery on top of an unreliable channel (it's an exercise, the unreliable channel explicitly drops some of its packets). I have an acks set that contains (address, sequence_number) pairs. When an ack is received over the channel it's added to the acks set and a condition variable is notified: msg, addr = self.unreliable_channel.recv() if isinstance(msg, Ack): with self.acks_cond: self.acks.add((addr, msg.ack)) print "{} got an ack: {} ({})".format

问题 I have two tables A and B with values below Table A X ------ 1 2 3 Table B X Y ------ ------ 1 A 2 A 3 A 1 B 2 B 1 C 3 D I need to find only the Y values from Table B which match All of the values in Table A. So for the above example the only Y value that matches is A (A has an X value of 1,2,and 3) 回答1: This is an example of a "set-within-sets" subquery. I like to approach this with aggregation and a having clause. select b.y from tableB b join tableA a on b.X = a.X group by b.y having count