/in/foo.cc: In function 'int main()':
/in/foo.cc:5:16: warning: unused variable 'e' [-Wunused-variable]
  int a,b,c,d=0,e,f,x[1001];
                ^
/in/foo.cc:5:18: warning: unused variable 'f' [-Wunused-variable]
  int a,b,c,d=0,e,f,x[1001];
                  ^