Converting C++ code to JAVA

Question

#include <iostream>

using namespace std;
int fun(int *k);

int main() {
    int i = 10, j = 10, sum1,sum2;
    sum1 = (i / 2) + fun(&i);
    sum2 = fun(&j) + (j / 2);
    cout<< sum1<< " "<<sum2<<endl;
}

int fun(int *k) {
    *k += 4;
    return 3 * (*k) - 1; 
}

I have to convert my code to Java Code I already converted but i couldn't find my mistake i cannot point variables to each other..

public class System{

   public static void main(String[] args) {
      int i = 10;
      int j = 10;
      int sum1 = (i / 2) + fun(k.value=i);
      int sum2 = fun(k.value=j) + (j / 2);
      System.out.println("%d%d",sum1,sum2 );
   }


   public static int fun(int k) {
      intobj k;
      int k= new k();
      k.value += 4;
      return 3 * (k.value) - 1; 
   }
}

This is my java code when i look at the int sum1 = (i / 2) + fun(k.value=i); int sum2 = fun(k.value=j) + (j / 2); part isn't true about point to true values. How can i solve that pointers problem. Thank you.

for those who havent seen `intobj` before (like me): http://www.th-mack.de/download/swisseph-doc/swisseph/IntObj.html — pennstatephil, Apr 13 '14 at 15:14
your code has UB. `sum2 = fun(&j) + (j / 2);` j is modified and read in one statement — RiaD, Apr 13 '14 at 15:24

score 1 · Accepted Answer · edited Jun 20 '20 at 09:12

The problem is that you're using ints instead of intobjs where you want to pass things around by reference (& in c++).

In your main function, you should try declaring i and j as intobjs and your parameter for fun, k should also be an intobj.

Code:

public class System{
   
   public static void main(String[] args) {
      intobj i = new intobj();
      i.value = 10;
      intobj j = new intobj();
      j.value = 10;
     int sum1 = (i.value / 2) + fun(i);
     int sum2 = fun(j) + (j.value / 2);
      System.out.println("%d%d",sum1,sum2 );
   }


   public static int fun(intobj k) {
      
      k.value += 4;
      return 3 * (k.value) - 1; 
   }
}

Converting C++ code to JAVA

1 Answers1

Code: