foo.cc: In function ‘int main()’:
foo.cc:5:17: warning: unused variable ‘c’ [-Wunused-variable]
    5 |         int a,b,c,d,e,f,g;
      |                 ^
foo.cc:5:19: warning: unused variable ‘d’ [-Wunused-variable]
    5 |         int a,b,c,d,e,f,g;
      |                   ^
foo.cc:5:21: warning: unused variable ‘e’ [-Wunused-variable]
    5 |         int a,b,c,d,e,f,g;
      |                     ^
foo.cc:5:23: warning: unused variable ‘f’ [-Wunused-variable]
    5 |         int a,b,c,d,e,f,g;
      |                       ^
foo.cc:5:25: warning: unused variable ‘g’ [-Wunused-variable]
    5 |         int a,b,c,d,e,f,g;
      |                         ^