enkelt spørgsmål: læse værdier ind i dobbelt vektor

Kode 

#include <vector>
#include <fstream>
#include <stdexcept>
#include <iostream>
using namespace std;

class Map
{
public:
   void loadSQSfile();
   int x_size, y_size;
   vector<vector<int> > domain;
   void Dump();
};

void Map::loadSQSfile ()
{
   ifstream SQS_file("Worldmap.sqs");
   if (!SQS_file) throw runtime_error("No file \\"Worldmap.sqs\\" was found!");

   SQS_file >> x_size >> y_size;
   domain.resize(x_size);
   for(int i = 0; i < x_size; i++)
      domain[i].resize(y_size);

   for (vector<vector<int> >::iterator x_iter = domain.begin(); x_iter != domain.end(); ++x_iter)
   {
      for (vector<int>::iterator y_iter = x_iter->begin(); y_iter != x_iter->end(); ++ y_iter)
      {
         SQS_file >> *y_iter;
       }
    }
}

void Map::Dump()
{
   for (vector<vector<int> >::iterator x_iter = domain.begin(); x_iter != domain.end(); ++x_iter)
   {
      for (vector<int>::iterator y_iter = x_iter->begin(); y_iter != x_iter->end(); ++ y_iter)
      {
         cout << *y_iter << " ";
      }
      cout << endl;
    }
}

int main()
{
   Map MyMap;
   MyMap.loadSQSfile();
   MyMap.Dump();
}

Kode 

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