foo.cc: In function 'int main()':
foo.cc:65:6: warning: unused variable 'ans' [-Wunused-variable]
  int ans=0;
      ^~~
foo.cc:44:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d%d",&n,&m);
  ~~~~~^~~~~~~~~~~~~~
foo.cc:45:29: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  for(int i=1;i<=n;i++) scanf("%d",d+i);
                        ~~~~~^~~~~~~~~~
foo.cc:49:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d%d%d",&a,&b,&c);
   ~~~~~^~~~~~~~~~~~~~~~~~~

自豪的采用HydroJudge(https://github.com/hydro-dev/Hydro)进行评测。