/in/foo.cc: In function 'int main()':
/in/foo.cc:31:17: warning: 'r2' may be used uninitialized in this function [-Wmaybe-uninitialized]
   31 |  cout<<r1<<' '<<r2<<endl;
      |                 ^~
/in/foo.cc:31:12: warning: 'r1' may be used uninitialized in this function [-Wmaybe-uninitialized]
   31 |  cout<<r1<<' '<<r2<<endl;
      |            ^~~