#include <iostream>
#include <string>
using namespace std;
int main() {
    string s1 = "hello";
    string s2 = "world";
    s1.append(s2, 1, 3);
    s1 += "!";
    cout << s1.size() << " " << s1.substr(5,3) << endl;
    return 0;
}