Reading from file and storing to 2D array

[Vagelis Fragoulakis]

I want to make a program that reads a map from a txt file and stores it in a two dimensional array of chars. The map is made of " * " and the size of it is 20x25. So this is what i came up with for which is important to mention that it works fine on Dev C++ but not on netbeans 7.

#include <cstdlib>
#include <iostream>
#include <fstream>
#include <string.h>
#include <time.h>


using namespace std;

class Map{
      private:
              char map[20][25]; //array of map to be stored
      public:
             Map(char *x){
                      char buffer[26];
                      int counter=0;
                      
                      ifstream map_p(x);
                      
                      if (!map_p.is_open())
                       { cout << "Error opening file"; exit (1); }
                       
                      for(int i=0; i<25; i++){
                                          map_p.getline(buffer,26);
                                          strcpy(*(map+counter),buffer);
                                          counter++;
                                          }
                                                                
                  }
          
      void printMap(){
           for(int i=0; i<20; i++){
                   for(int j=0; j<25; j++){
                           cout<<map[i][j];
                           }
                           cout<<endl;
                           }
                           }
      };


int main(int argc, char *argv[])
{
    char *y;
    strcpy(y,"map3.txt");
    Map x(y);
    x.printMap();
    system("PAUSE");
    return EXIT_SUCCESS;
}

I feel that something is wrong with the pointers because if i use strings instead of chars the map is printed fine on netbeans but i can't store it in the array.

[coder777]

Line 23 is wrong. The value should be 20.

You don't need count.

Line 25: strcpy stores the trailing 0 so you need strncpy http://www.cplusplus.com/reference/clibrary/cstring/strncpy/

Line 25 should lool like this: strncpy(map[i],buffer,25);

[...] if i use strings instead of chars the map is printed fine on netbeans but i can't store it in the array.

Why not?

[Vagelis Fragoulakis]

I apologize i didn't elaborate enough. I want to have instant access on any part of the array to insert new characters and strings don't work for me. I found a solution and i don't know if it's the best one but it seems to work fine. Thanks for pointing out the mistake on line 23.

#include <iostream>
#include <fstream>


class Map {

    char map[20][25];

public:

    Map(char *x) {

        std::ifstream map_p(x); 


        if (!map_p.is_open()) {

            //throw exception to notify main

            throw std::invalid_argument("file could not be opened");

        }

        else {

            char buffer[27];
            int i = 0;

            while(i < 20) { 

                map_p.getline(buffer,27);

                for (int j=0;j<25;j++)

                    map[i][j]=buffer[j];
                i++;

            }

            map_p.close();

        }

 

    }

    void printMap() {

        for(int i=0; i<20; i++) {

            for(int j=0; j<25; j++) {

            std::cout<<map[i][j];

        }

            std::cout<<std::endl;

     }

    }

};

What i still don't get is why the buffer size needs to be 27 or more for it to work properly (i found out about that by chance).