Thread: all possible combinations of an array

you mean somthing like:

Code:

int data[ 4 ] = { 1, 2, 3, 4 };

std::cout << "Sum is: " << data[ 0 ] + data[ 1 ] + data[ 2 ] + data[ 3 ] << std::endl;

I am only guessing here

thank you for your replies,
tabstop your idea was great thank you. I tried to make a code that makes that binairy odometer, it works partly, because after the 5 digits it gives rubbish information. The problem is that he has to go up to 32000000 digits. Is it possible with this program structure, if not could someone tell me how it has to be done? thank you in advance.
here is the code:

Code:

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



int main()
{
    long getal;
    
    cin>>getal;
    double kopie=getal;
    long hoi=pow(2,kopie);
    
    cout<<hoi<<endl;
    bool tabel[getal][hoi];
    for(int n=0;n<=hoi;n++)
    {
        for(int t=0;t<=getal;t++)
        {
            tabel[t][n]=false;
        }
    }
    
    for(int n=0;n<=(hoi);n++)
    {
        if (n==0)
        {n++;}
        for(int t=0;t<=getal;t++)
        {
            tabel[t][n]=tabel[t][n-1];
        }
        for(int ok=0, h=0;ok==0;)
        {
            if (tabel[h][n]==false)
            {tabel[h][n]=true;ok=1;}
            else
            {
                tabel[h][n]=false;
                h++;
            }
        }
    }
    
    for(int n=0;n<=hoi;n++)
    {
        for(int t=0;t<=(getal-1);t++)
        {
            if(tabel[t][n]==true)
            {cout<<1;}
            else
            {cout<<0;}
        }
        cout<<endl;
    }
    char stop;
    cin>>stop;
    return(0);
}

sorry for the big main but I am not that good in programming and I hadn't that much time to put everything in functions

A hint is that the binary "odometer" is just a number being incremented by one. It probably won't be very efficient - but I guess efficiency is not the concern here - but you might just use an integer and check which bits are set. std::bitset might be handy for that.

32000000 digits? 32000000 elements in the array you want all combinations of?

Well, if you ever get your program working, I'll see you next decade.