foo.cc: In function 'int main()':
foo.cc:132:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d",&n);
  ~~~~~^~~~~~~~~
foo.cc:134:16: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   int u,v;scanf("%d%d",&u,&v);
           ~~~~~^~~~~~~~~~~~~~
foo.cc:137:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d",&m);
  ~~~~~^~~~~~~~~
foo.cc:139:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d%d",f+i,p+i);
   ~~~~~^~~~~~~~~~~~~~~~
foo.cc:142:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d%d",&q,&k);
  ~~~~~^~~~~~~~~~~~~~
foo.cc:146:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d%d%d",&opt,&x,&y);
   ~~~~~^~~~~~~~~~~~~~~~~~~~~

[Hydro](https://hydro.ac)提供评测服务