Copy only unique elements in a vector into another vector : unique copy « STL Algorithms Modifying sequence operations « C++ Tutorial

1. C++ Tutorial
2. STL Algorithms Modifying sequence operations
3. unique copy

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

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

int main()
{
   const int SIZE = 10;
   int a1[ SIZE ] = { 1, 3, 5, 7, 9, 1, 3, 5, 7, 9 };
   std::vector< int > v1( a1, a1 + SIZE ); // copy of a
   std::ostream_iterator< int > output( cout, " " );

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

   std::vector< int > results1;

   std::unique_copy( v1.begin(), v1.end(), std::back_inserter( results1 ) );
   cout << "\nAfter unique_copy results1 contains: ";
   std::copy( results1.begin(), results1.end(), output );

   return 0;
}

Vector v1 contains: 1 3 5 7 9 1 3 5 7 9
After unique_copy results1 contains: 1 3 5 7 9 1 3 5 7 9