#include<bits/stdc++.h>
using namespace std;
map<string,int>mp;
int n,sum;
int main(){
	cin>>n;
	for(int i=1;i<=n;i++){
		int x;
		cin>>x;
		if(x==1){
			string s;
			int k;
			cin>>s>>k;
			mp[s]=k;
			cout<<"OK"<<endl;
			sum++;
		}
		else if(x==2){
			string s;
			cin>>s;
			if(mp[s]==0){
				cout<<"Not found"<<endl;
			}
			else{
				cout<<mp[s]<<endl;
			}
		}
		else if(x==3){
			string s;
			cin>>s;
			if(mp[s]==0){
				cout<<"Not found"<<endl;
			}
			else{
				mp[s]=0;
				cout<<"Deleted successfully"<<endl;
				sum--;
			}
		}
		else{
			cout<<sum<<endl;
		}
	}
	return 0;
}

为啥连一个测试点都没对
我快崩溃了
请求各位大佬赐教！！！