STL vector sorting example

Here's a simple STL vector sorting example code in c++. a vector container is sorted by using sort() from <algorithm>, . It just traverses the items in a given STL list container.
[STL vector sorting example]

//Sorting a vector with 9 integers

#include <iostream.h>

#include <vector>

#include <algorithm>

void print( vector<int> ) ;//utility function outputs a $container

int main()

{

vector<int> a;

// Place 9,8,7,6,5,4,3,2,1 into the vector

for(int i=0; i<9;++i)

a.push_back(9-i);// put new element after all the others

print(a); // elements of a are (9,8,7,6,5,4,3,2,1)

sort( a.begin(), a.end() ); //in the STL <algorithm> library

print(a); // elements are nor in order.

}

void print( vector<int> a)

{

for(vector<int>::iterator ai=a.begin(); ai!=a.end(); ++ai)

cout << *ai << " ";

cout << endl;

cout << "----------------"<<endl;

}