/in/foo.cc: In function 'void insert(long long int)':
/in/foo.cc:129:8: error: reference to 'rank' is ambiguous
  int k=rank(x,rt);
        ^~~~
/in/foo.cc:87:5: note: candidates are: long long int rank(long long int, long long int)
 int rank(int x,int rt)//查找x数的排名 
     ^~~~
In file included from /usr/include/c++/6/bits/move.h:57:0,
                 from /usr/include/c++/6/bits/nested_exception.h:40,
                 from /usr/include/c++/6/exception:173,
                 from /usr/include/c++/6/ios:39,
                 from /usr/include/c++/6/istream:38,
                 from /usr/include/c++/6/sstream:38,
                 from /usr/include/c++/6/complex:45,
                 from /usr/include/c++/6/ccomplex:39,
                 from /usr/include/x86_64-linux-gnu/c++/6/bits/stdc++.h:52,
                 from /in/foo.cc:1:
/usr/include/c++/6/type_traits:1482:12: note:                 template<class> struct std::rank
     struct rank
            ^~~~
/in/foo.cc: In function 'int main()':
/in/foo.cc:171:31: error: reference to 'rank' is ambiguous
    pair<int,int> tmp=split(rt,rank(minn-summ-1,rt));
                               ^~~~
/in/foo.cc:87:5: note: candidates are: long long int rank(long long int, long long int)
 int rank(int x,int rt)//查找x数的排名 
     ^~~~
In file included from /usr/include/c++/6/bits/move.h:57:0,
                 from /usr/include/c++/6/bits/nested_exception.h:40,
                 from /usr/include/c++/6/exception:173,
                 from /usr/include/c++/6/ios:39,
                 from /usr/include/c++/6/istream:38,
                 from /usr/include/c++/6/sstream:38,
                 from /usr/include/c++/6/complex:45,
                 from /usr/include/c++/6/ccomplex:39,
                 from /usr/include/x86_64-linux-gnu/c++/6/bits/stdc++.h:52,
                 from /in/foo.cc:1:
/usr/include/c++/6/type_traits:1482:12: note:                 template<class> struct std::rank
     struct rank
            ^~~~