Compare Vector V1 and V2 for equality

Here are the ways to compare two vectors.

Method 1:

 
#include < iostream >
using std::cout;
using std::endl;

#include < algorithm >
#include < vector >
#include < iterator >

int main()
{
   int a1[ 10 ] = { 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 };
   int a2[ 10 ] = { 1, 2, 3, 4, 9, 6, 7, 8, 9, 10 };
   std::vector<> v1( a1, a1 + 10 );
   std::vector<> v2( a1, a1 + 10 );
   std::vector<> v3( a2, a2 + 10 );
   std::ostream_iterator<> output( cout, " " );

   cout << "Vector v1 contains: ";    
   std::copy( v1.begin(), v1.end(), output );    
   cout << "\nVector v2 contains: ";
   std::copy( v2.begin(), v2.end(), output );
   cout << "\nVector v3 contains: ";
   std::copy( v3.begin(), v3.end(), output );

   // compare vectors v1 and v2 for equality    
   bool result = std::equal( v1.begin(), v1.end(), v2.begin() );    
   cout << "\n\nVector v1 " 
        << ( result ? "is" : "is not" )
        << " equal to vector v2.\n"
        return 0;
}

Method 2:

Overload the == operator for comparision

 

inline bool operator == (const std::vector< std::string >, 
                         const std::vector< std::string >)
{
    if (lhs.size() != rhs.size())
        return false;

    int count = lhs.size();
    std::vector< std::string >::const_iterator lhsi = lhs.begin();
    std::vector< std::string >::const_iterator rhsi = rhs.begin();
    while (count--)
    {
        if ( *lhsi != *rhsi)
            return false;
        lhsi++; rhsi++;
    }
    return true;
}