样例过了但是全红
#include <iostream>
#include <map>
#include <string.h>
using namespace std;
map<string,int> mp;
int type,n;
string s;
int main()
{
cin>>n;
for(int i=0;i<n;i++)
{
cin>>type;
if(type==0)return 0;
else if(type==1)
{
cin>>s;
int x;
cin>>x;
mp[s]=x;
cout<<"OK\n";
}
else if(type==2){
cin>>s;
if(!mp.count(s)){
cout<<"Not found\n";
}else{
cout<<mp[s]<<endl;
}
}else if(type==3){
cin>>s;
if(mp.count(s)){
mp.erase(s);
cout<<"Deleted successfully"<<endl;
}
else{
cout<<"Not found\n"<<endl;
}
}else if(type==4)cout<<mp.size()<<endl;
}
}