/in/foo.cc: In function 'int main()':
/in/foo.cc:4:9: warning: unused variable 'a' [-Wunused-variable]
    4 |     int a,b,c,d,e,f,n;
      |         ^
/in/foo.cc:4:11: warning: unused variable 'b' [-Wunused-variable]
    4 |     int a,b,c,d,e,f,n;
      |           ^
/in/foo.cc:4:13: warning: unused variable 'c' [-Wunused-variable]
    4 |     int a,b,c,d,e,f,n;
      |             ^
/in/foo.cc:4:15: warning: unused variable 'd' [-Wunused-variable]
    4 |     int a,b,c,d,e,f,n;
      |               ^
/in/foo.cc:4:17: warning: unused variable 'e' [-Wunused-variable]
    4 |     int a,b,c,d,e,f,n;
      |                 ^
/in/foo.cc:4:19: warning: unused variable 'f' [-Wunused-variable]
    4 |     int a,b,c,d,e,f,n;
      |                   ^