/in/foo.cc: In function 'int main()':
/in/foo.cc:6:10: warning: 'n' is used uninitialized [-Wuninitialized]
    6 |         a=n%10;
      |         ~^~~~~
/in/foo.cc:5:13: note: 'n' was declared here
    5 |         int n,a,b,c;
      |             ^