#include <iostream>
#include <string>
using namespace std;

int main()
{
    string s1 = "Have a nice day";
    string s2, s3, s4, s5, s6;

    s2.assign(s1);
    s3.assign(s1,7,4);
    s4.assign("Hey");
    s5.assign(s1.c_str(),3);
    s6.assign(5,'x');
    cout << s2 << endl << s3 << endl << s4 << endl << s5 << endl << s6 << endl << endl;

    s2.append(s1);
    s3.append(s1,7,4);
    s4.append("Hey");
    s5.append(s1.c_str(),3);
    s6.append(5,'x');
    cout << s2 << endl << s3 << endl << s4 << endl << s5 << endl << s6 << endl << endl;

    s2.erase();
    s3.erase(4);
    s4.erase(3,2);
    s5.erase(s5.begin()+1,s5.begin()+4);
    cout << s2 << endl << s3 << endl << s4 << endl << s5 << endl << endl;

    s2 = s1;
    s3 = "very ";

    s2.insert(7,s3);
    cout << s2 << endl;
    s2.insert(s2.find("nice"),"VERY ");
    cout << s2 << endl << endl;

    s2.push_back('!');
    cout << s2 << endl << endl;

    s2.replace(s2.find("very VERY"),string("excellent").size(),"excellent");
    cout << s2 << endl << endl;

    s2.replace(s2.find("excellent"),string("excellent nice").size(),"swell");
    cout << s2 << endl << endl;

    s1.swap(s2);
    cout << s1 << endl << s2 << endl << endl;

    s1.pop_back();
    cout << s1 << endl;
}