string functions fun

#include <iostream>
#include <string> //For string functions.
#include <stdlib.h> //For system()

using namespace std;

int main()
{
    string x;
    x.append("lol");
    cout << x << endl;

    string y;
    y.append("Hey");
    cout << y << endl;
    system("pause");
    system("cls");
    y.erase(1);
    cout << y << endl;

    string z;
    z.append("Hello");
    cout << z.at(3) << endl;
}