Discards excess capacity.
void shrink_to_fit(
);
Example
// vector_shrink_to_fit.cpp
// compile with: /EHsc
#include <vector>
#include <iostream>
int main( )
{
   using namespace std;   
   vector <int> v1;
   //vector <int>::iterator Iter;
   v1.push_back( 1 );
   cout << "Current capacity of v1 = " 
      << v1.capacity( ) << endl;
   v1.reserve( 20 );
   cout << "Current capacity of v1 = " 
      << v1.capacity( ) << endl;
   v1.shrink_to_fit();
   cout << "Current capacity of v1 = " 
      << v1.capacity( ) << endl;
}
Current capacity of v1 = 1 Current capacity of v1 = 20 Current capacity of v1 = 1
Requirements
Header: <vector>
Namespace: std