/in/foo.cc: In function 'int main()':
/in/foo.cc:7:19: warning: unused variable 'u' [-Wunused-variable]
  char str[100005],u,f,d;
                   ^
/in/foo.cc:7:21: warning: unused variable 'f' [-Wunused-variable]
  char str[100005],u,f,d;
                     ^
/in/foo.cc:7:23: warning: unused variable 'd' [-Wunused-variable]
  char str[100005],u,f,d;
                       ^