/in/foo.cc: In function 'int main()':
/in/foo.cc:18:6: warning: unused variable 'a' [-Wunused-variable]
  int a,b,c=0,d,i,j,sum;
      ^
/in/foo.cc:18:8: warning: unused variable 'b' [-Wunused-variable]
  int a,b,c=0,d,i,j,sum;
        ^
/in/foo.cc:18:14: warning: unused variable 'd' [-Wunused-variable]
  int a,b,c=0,d,i,j,sum;
              ^
/in/foo.cc:18:16: warning: unused variable 'i' [-Wunused-variable]
  int a,b,c=0,d,i,j,sum;
                ^