9bac 40

#include <iostream>

using namespace std;

int main() {

 unsigned c1,c2,c3,c4,nr;

 for (c1=1;c1<9;c1++)
 for (c2=c1+1;c2<=9;c2++)
 for (c3=0;c3<=c2-1;c3++)
  for (c4=c3+1;c4<=9;c4++)
{
    nr=c1*1000+c2*100+c3*10+c4;
    cout<<nr<<",";
}

 return 0;
}