STL_<set>

7
add 1
add 1
ask 1
ask 2
del 2
del 1
ask 1

1
2
1 2
0 0
0
2
1 0

#include <iostream>
#include <set>
using namespace std;

int main()
{
    multiset<int>a;
    set<int>v;
    char s[5];
    int n, p;
    multiset<int>::iterator m;
    cin >> n;
    for (int i = 0; i < n; ++i) {
        cin >> s >> p;
        switch (s[1]) {
        case ‘d‘:
            a.insert(p);
            v.insert(p);
            cout << a.count(p) << endl;
            break;
        case ‘e‘:
            cout << a.count(p) << endl;
            m = a.find(p);
            while (m != a.end()) {
                a.erase(m);
                m = a.find(p);
            }
            break;
        case ‘s‘:
            if (v.find(p) == v.end())cout << 0;
            else cout << 1;
            cout << ‘ ‘ << a.count(p) << endl;
            break;
        }
    }

    return 0;
}