string

#include <iostream>
#include <string>

using namespace std;


void getStr(string &str , char);
void Print_length(string &str, char );
void Print_Char_Str(string a);
void Comp_length (string a, string b);
void Swap_Str( string &a, string &b);
int main(void)
{
    string a;
    string b;
    getStr(a,'a');
    getStr(b,'b');
    Print_length(a,'a');
    Print_length(b,'b');
    Comp_length (a,b);
    cout << endl << a.compare(b) << endl;
    if ( a > b)
    {
        Swap_Str(a,b);
        cout << "DO a > b nen hoan vi 2 chuoi a b" << endl;
        cout << "chuoi a: "<< a << endl;
        cout << "chuoi b: " << b << endl;
    }

    string c = a;
    c = c+b;
    cout << "chuoi c: " << c;
    string d = c.string( a.length(), a.length()+b.length());

    return 0;
}

void getStr(string &str, char a)
{

    cout << "Nhap Chuoi " << a << ": ";
    getline(cin, str);
}
void Print_length(string &str, char a)
{
     int k = str.length();
    cout << endl << "Do dai chuoi " << a <<": " << k;
}

void Print_Char_Str(string a)
{
    int l = a.length();
    cout << endl;
    for ( int i = 0; i < l; i++)
        cout << a[i] << ".";
    cout << endl;
}

void Comp_length(string a, string b)
{
    int l1 = a.length();
    int l2 = b.length();
    if ( l1 > l2)
    {
        Print_Char_Str(a);
        return;
    }
    if ( l1 == l2)
    {
        Print_Char_Str(a);
        Print_Char_Str(b);
        return;
    }
    if ( l1 < l2)
    {
        Print_Char_Str(b);
        return;
    }
}

void Swap_Str( string &a, string &b)
{
    string Temp = a;
    a = b;
    b = Temp;
}