#include <bits/stdc++.h>
// #include <windows.h>
#define int long long
using namespace std;

signed main() 
{
    // SetConsoleOutputCP(65001);
    int n;
    cin>>n;
    map<string ,int>mp;
    while(n--)
    {
        // cout<<endl<<"size:   "<<mp.size()<<endl;
        int a;
        cin>>a;
        if(a==1)//insert
        {
            string name;
            int score;
            cin>>name>>score;
            mp[name]=score;
            cout<<"OK\n";
        }
        if(a==2)//search
        {
            string name;
            cin>>name;
            if(mp.count(name))
            {
                cout<<mp[name];
            }
            else{
                cout<<"Not found";
            }
            cout<<endl;
        }
        if(a==3)//dele
        {
            string name;
            cin>>name;
            if(mp[name])
            {
                mp.erase(mp.find(name));
                cout<<"Deleted successfully";
            }
            else
            {
                cout<<"Not found";
            }
            cout<<endl;
        }
        if(a==4)//sumup
        {
            cout<<mp.size()<<endl;
        }
    }
    return 0;
}

求大佬救命，看了一晚上了，找出了map查询的时候空的会自增，解决了，但是提交的时候又是0分 由于看样例的次数在别的题目上用掉了，我也不知道我错在哪里了