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returning a 2d array from a function

kassik (23)
Hi every body
I am very beginner and I am trying to write a simple code.
I want to call a function doing a few works in a 2d array and then return it's new values to the main function without using pointer.
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#include <iostream>
#include<math.h>
#include<stdlib.h>
#include<string>
#include<fstream>
#include<sstream>
#include <iomanip>


#define PI 3.14159265
int scr[216][216];
using namespace std;


int function (int scr[216][216], double x1,double y1,double x2,double y2,double teta);

//void function (int scr[1296][1296],int);
//void function (int x1,int y1,int x2,int y2,int teta);

int main() {


    double x,y,x1,x2,y1,y2,teta,alpha;
int p,q;


        ofstream myfile;
         myfile.open("pic kock program6.pgm");
   myfile<< "P2\n";
    myfile<< "# Shows the word (example from Netpbm main page on ";
   myfile<< "PGM)\n";
  myfile<< "216 216 \n";
  myfile<< "15\n";



  x1=10;
  y1=10;
  x2=200;
  y2=10;

    alpha=0;// the angle between first line and horizental axis
  teta=0;

    int i=0,j=0;

  for(j=0;j<216;j++)
  for(i=0;i<216;i++)
  scr[j][i]=0; // clears whole screen

scr=function(scr,x1,y1,x2,y2,teta);


        for(i=0;i<216;i++)

  {
         myfile<<"\n";
        for(j=0;j<216;j++)
        myfile<<scr[i][j]<<" ";
          }
                myfile.close();


 return 0;
}


int function (double x1,double y1,double x2,double y2,double teta)
{

    double x,y,alpha;
int p,q,i,j;

        for (i=0 ;i<(floor((x2-x1)/3)); i++) {
        j=i* tan(teta*PI/180);
        p= floor(y1+j);
        q=floor(x1+i);
        scr[p][q]=15;
    }




for (i=floor(2*(x2-x1)/3) ;i<floor(x2-x1); i++) {
        j=i* tan(teta*PI/180);
        p=floor(y1+j);
        q=floor(x1+i);
        scr[p][q]=15;
    }

    for (i=0 ;i<floor((x2-x1)/3); i++)
   {
       j=i* tan(teta*PI/180);
       x=i*cos((60+teta)*PI/180)-j*sin((60+teta)*PI/180);
       y=i*sin((60+teta)*PI/180)-j*cos((60+teta)*PI/180);


   p=floor(y1+y);
   q=floor(x+x1+(x2-x1)/3);
   scr[p][q]=15;

   }

    for (i=0 ;i<floor((x2-x1)/3); i++)
   {

       j=i* tan(teta*PI/180);

       x=i*cos((120+teta)*PI/180)-j*sin((120+teta)*PI/180);

      y=i*sin((120+teta)*PI/180)-j*cos((120+teta)*PI/180);
      p=floor(y+y1);
      q=floor(x+x1+2*(x2-x1)/3);
      scr[p][q]=15;

   }
return scr[216][216];
}





any help is appreciated.
Last edited on
JLBorges (13770)
> I want to call a function doing a few works in a 2d array and then return it's new values
> without using pointer.

Pass the array by reference.

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constexpr int M = 216, N = 216 ;

typedef int array_type[M][N] ;

void function( array_type& array, double x1, double y1, double x2, double y2, double teta )
{
    // modify the array
}

int main()
{
    int my_array[M][N] ;
    // ..
    
    function( my_array, 1, 2, 3, 4, 5 ) ;
    // use modified my_array
}
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