/in/foo.cc: In function 'int main()':
/in/foo.cc:19:18: warning: 'a' may be used uninitialized [-Wmaybe-uninitialized]
   19 |         cout<<a<<" "<<b;
      |                  ^~~
/in/foo.cc:8:13: note: 'a' was declared here
    8 |         int a,b,c,d;
      |             ^