/in/foo.cc: In function 'int main()':
/in/foo.cc:15:15: warning: 'sum' may be used uninitialized [-Wmaybe-uninitialized]
   15 |         cout<<sum;
      |               ^~~
/in/foo.cc:5:19: note: 'sum' was declared here
    5 |         int a,b,c,sum;
      |                   ^~~