/in/foo.cc: In function 'int main()':
/in/foo.cc:20:23: warning: 'c' may be used uninitialized [-Wmaybe-uninitialized]
   20 |                 cout<<c;
      |                       ^
/in/foo.cc:5:19: note: 'c' was declared here
    5 |         int k,a,b,c;
      |                   ^