将用 C++ 编写的程序代码迁移到 C# - 相当于 `set<ii> ::迭代器？</ii>

Question

I have a program written in C++ that process To place students to departments in order of preference and by their scores. Then I want to migrate this code to C# language. I converted all but the PlaceStudents() function is not complete. How can I find equivalent of set<ii>::iterator in C#?

using namespace std;
typedef pair<int, int>   ii;

const int studentCount = 200, departmentCount = 40, preferenceCount = 24, scoreKind = 18;

struct Student {
    string name;
    int order[scoreKind]; // order[i] => student i. scoreKind order (order of student in score kind)
    int preference[preferenceCount]; // student's preference list
    int applicationCount; // student's application count
} student[studentCount + 7];

struct Department {
    string name;
    int quota; // acceptable max student count by Department
    int scoreKind; // accepted score kind by Department
    set<ii> S; // temporary accepted student by Department. (order, index) of student
} department[departmentCount + 7];

void PlaceStudents() {
    queue<int> Q; // students queue
    fori(i, 0, studentCount) {
        Q.push(i); // in the begining add all students to queue
    }
    while (!Q.empty()) {
        int id = Q.front();
        Q.pop();
        Student *a = &student[id]; // kuyrugun onundeki ogrenci
        Department *b = &department[a->preference[a->applicationCount]]; // department that next preference order of this student 
        b->S.insert({ a->order[b->scoreKind],id }); // add student to department
        if (b->S.size() > b->quota) { // If student count more than the quota 
            set<ii> ::iterator it = b->S.end();
            it--; // last element of set
            int x = it->second; // index of worst scored student 
            b->S.erase(it); // delete worst scored student
            student[x].applicationCount++; // increment students applicationCount
            if (student[x].applicationCount < preference) // if student is not rejected from all preferences
                Q.push(x); // add student to queue for next proses
        }
    }
}

Converted PlaceStudents Function to C# is below

public static void PlaceStudents()
{
    Queue<int> Q = new Queue<int>(); // students queue
    for (int i = 0; i < studentCount; ++i)
    {
        Q.Enqueue(i); // in the begining add all students to queue
    }
    while (Q.Count > 0)
    {
        int id = Q.Peek();
        Q.Dequeue();
        Student a = student[id]; // the student in front of the queue
        Department b = department[a.preference[a.applicationCount]]; // department that next preference order of this student
        b.S.Add(new Tuple<int, int>(a.order[b.scoreKind], id)); // add student to department
        if (b.S.Count > b.quota)
        { // If student count more than the quota
            SortedSet<Tuple<int, int>> iterator it = b.S.end(); // I can't convert from here  until end.
            it--; // last element of set
            int x = it.second; // index of worst scored student
            b.S.Remove(it); // delete worst scored student
            student[x].applicationCount++; // increment students applicationCount
            if (student[x].applicationCount < preference) // if student is not rejected from all preferences
            {
                Q.Enqueue(x); // add student to queue for next loop
            }
        }
    }
}

Answer 1

I do not think you should be that literal when converting code

        set<ii> ::iterator it = b->S.end();
        it--; // last element of set
        int x = it->second; // index of worst scored student 
        b.S.Remove(it); // delete worst scored student

The goal of all this is apparently to extract and remove the last element of the list. The equivalent to iterators in.Net is IEnumerator , but this is a bit simpler and more restrictive than c++ iterators. The closest equivalent would use Linq to get the last item:

 var item = b.S.Last(); // Get last item, or throws if empty
 var b.S.Remove(item); // remove item