/in/foo.cc: In function 'int main()':
/in/foo.cc:47:13: warning: variable 'next' set but not used [-Wunused-but-set-variable]
         int next;
             ^~~~
/in/foo.cc:67:28: warning: 'cost' may be used uninitialized in this function [-Wmaybe-uninitialized]
     printf("%.2lf\n", cost);
                            ^