text: #include <iostream>
  #include <cmath>
  using namespace std;
  int main(){
      int a,b,c,n;
      n = 0;
      for (a = 1; a <= 4; ++a){
          for (b = 1; b <= 4; ++b){
              for (c = 1; c <= 4; ++c){
                  if (a!=b && b!=c && a!=c) cout << a << b << c<<endl;
              }
          }
      }
      //cout << n;
      //system("pause > nul");
  }