/in/foo.cc: In function 'int main()':
/in/foo.cc:20:15: warning: 'k' may be used uninitialized [-Wmaybe-uninitialized]
   20 |         cout<<k;
      |               ^
/in/foo.cc:5:21: note: 'k' was declared here
    5 |         int a,b,n,i,k;
      |                     ^