#include <iostream>
#include<string>
using namespace std;
int main()
{
string s="abc";
string s1,s2,s3,s4;
s1=s.substr(0,2);
cout<<s1<<endl;
s2=s.insert(0,2,'a');
cout<<s2<<endl;
s3=s.insert(1,"hh");
cout<<s3<<endl;
s4=s.erase(0,4);
cout<<s4<<endl;
system("pause");
	return 0;
}