/in/foo.cc: In function 'int main()':
/in/foo.cc:19:62: error: 'scanf' was not declared in this scope
         scanf("%lld %lld %lld %lld",&time,&speed,&pos,&target);
                                                              ^
/in/foo.cc:30:26: error: 'printf' was not declared in this scope
         printf("%lld",ans);
                          ^