How to port a Perl class containing a static hash of string => ref_to_array_of_strings pairs to C++?

I'm new to C++, but basically what I want to do is create a C++ class that contains a private static const hash of string => array_ref_of_strings pairs and just dump it to stdout. Is not much to ask is it? I've create 2 examples of code below. This first one is the Perl example. The second one is my inexperienced idea of how it should be done in C++ which is probably full of inefficiencies and other weirdness. It works, but I'm not sure what I'm doing so please advise. I've added comments and questions to the C++ example. One thing I really want to know is how to declare a variable map (hash) variable as NULL and define it later (Test::_getFood()  implementation).

-Craig Manley.

============ This the example Perl script containing a Test class. ===============
#!/usr/bin/perl -w
use strict;

# main
my $t = new Test();
$t->Dump();
exit(0);


# Declare the Test class and it's methods.
package Test;

my $static_food;

sub new {
  my $proto = shift;
  my $class = ref($proto) || $proto;
  if (!defined($static_food)) {
    $static_food = {
                      'fruit'      => ['apples', 'bananas', 'oranges'],
                    'vegetables' => ['peas', 'carrots']
                   };
  }
  my $self = {'_food' => $static_food};
  bless($self,$class);
  return $self;
}

sub Dump {
  my $self = shift;
  my $food = $self->{'_food'};
  foreach my $key (keys %{$food}) {
    print "$key:\n";
    my $vals = $food->{$key};
    foreach my $val (@{$vals}) {
      print "\t" . $val . "\n";
    }
  }
}

1;



============ This how I ported it to C++. ===============
#include <map>
#include <vector>
#include <iostream>
using namespace std;

typedef map<string, vector<string> > MSVS;
typedef MSVS::iterator IMSVS;


//////// Interface ////////
class Test {
  public:
    // Contructor.
    Test();
    // Dumps contents.
    void dump();
  protected:
    // Returns a static 'food' map.
    MSVS _getFood();
};


//////// Implementation ////////

// Contructor.
Test::Test() {
}


// Dumps contents.
void Test::dump() {
  MSVS food = this->_getFood(); // Is this assignment efficient (i.e. just a pointer copy)?
  for (IMSVS iter = food.begin(); iter != food.end(); iter++) {
    cout << iter->first << ":\n";
    vector<string> values = iter->second; // Is this assignment efficient (i.e. just a pointer copy)?
    for (int i = 0; i < values.size(); i++) {
      cout << "\t" << values[i] << "\n";
    }
  }
}


// Returns a static 'food' map.
MSVS Test::_getFood() {
  // Why can't I do this?:
  // static MSVS food = NULL;
  // if (food == NULL) {
  //   food = new MSVS();
  //   ...
  // }
  //
  static bool initialized = false;
  static MSVS food;
  if (!initialized) {
    food["fruit"].push_back("apples");
    food["fruit"].push_back("bananas");
    food["fruit"].push_back("oranges");
    food["vegetables"].push_back("peas");
    food["vegetables"].push_back("carrots");
    initialized = true;
  }
  return food;
}



//////// Run it... ////////
int main() {
  Test* t = new Test();
  t->dump();
  return 0;
}


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