C++, How do i write cout output side by side?

Question

As mentioned in the title, I do not know how to format my std::cout output such that the inner for-loop writes in "rows" but the outer for-loop produces columns.

My Code:

#include <iostream>
#include <iomanip>
using namespace std;

class LoopTest
{   //Access specifier
    public:
        //Data Members
        int outer_size = 2;
        int inner_size = 3;

    //Memberfunction
    int testing()
    {
    freopen("/home/user/training/exercise/e0/TESTPROGRAM_OUTPUT.dat", "w", stdout); //redirect output to file

        for(int i = 0; i <= outer_size; i++)
        {   
            cout <<  " number: " << i;
            for(int j = 0; j <= inner_size; j++)
            {
                cout << " j*(j*i): " << j*(j*i); 
                cout << "  ";
                cout << "\n";
            }

        }
        fclose(stdout);
        return 0;

    }
};

The code shown above produces the following output:

     number: 0 j*(j*i): 0  
 j*(j*i): 0  
 j*(j*i): 0  
 j*(j*i): 0  
 number: 1 j*(j*i): 0  
 j*(j*i): 1  
 j*(j*i): 4  
 j*(j*i): 9  
 number: 2 j*(j*i): 0  
 j*(j*i): 2  
 j*(j*i): 8  
 j*(j*i): 18

As mentioned, the ideal output would be:

 number: 0 j*(j*i): 0   number: 1 j*(j*i): 0   number: 2 j*(j*i): 0
 j*(j*i): 0             j*(j*i): 1             j*(j*i): 2
 j*(j*i): 0             j*(j*i): 4             j*(j*i): 8
 j*(j*i): 0             j*(j*i): 9             j*(j*i): 18

You need something like [this](https://stackoverflow.com/questions/14765155/how-can-i-easily-format-my-data-table-in-c) and you have to compute each row in the same iteration. — NathanOliver, Nov 08 '18 at 14:10
you could store the columns and then print them line by line. You cannot print columns directly — 463035818_is_not_an_ai, Nov 08 '18 at 14:11
First of all write and format the text properly, secondly format your code properly: the second loop was not indented. — roschach, Nov 08 '18 at 14:33

score 1 · Answer 1 · answered Nov 08 '18 at 14:11

You have to interleave your outputs, first outputting all your first line, and the second...

   for(int i = 0; i <= outer_size; i++)
   {   
        cout <<  " number: " << i << "\t"; // Add the tabs necessary
   }
   for(int j = 0; j <= inner_size; j++)
   {
       for(int i = 0; i <= outer_size; i++)
       {   
            // The the first result line
       }
    }

score 1 · Accepted Answer · answered Nov 08 '18 at 14:35

Change the order of for loops.

You can do something like this:

#include<iostream>
#include<cmath>
using namespace std;
int main (int argc, char* argv[])
{
   int outer_size=2, inner_size=3;
   int j=0;
   for(int i = 0; i <= outer_size; i++)
   {   
        cout <<  " number: " << i;
    cout << " j*(j*i): " << j*(j*i)<<"\t";
   }
   std::cout<<endl;

   for( j = 1; j <= inner_size; j++)
   {

        for (int i=0; i<=outer_size; i++)
        {   
        cout << " j*(j*i): " << j*(j*i)<<"\t\t";
        }
       std::cout<<endl;
   } 

    return 0;
}

Producing this output on Terminal:

 number: 0 j*(j*i): 0    number: 1 j*(j*i): 0    number: 2 j*(j*i): 0   
 j*(j*i): 0              j*(j*i): 1              j*(j*i): 2     
 j*(j*i): 0              j*(j*i): 4              j*(j*i): 8     
 j*(j*i): 0              j*(j*i): 9              j*(j*i): 18

C++, How do i write cout output side by side?

2 Answers2