运行 ID: 42773

Main.cc: In function ‘int main()’:
Main.cc:19:2: error: reference to ‘rank’ is ambiguous
  rank(a, 5);//成绩从高往低的一个排序 
  ^~~~
Main.cc:4:6: note: candidates are: void rank(int*, int)
 void rank(int b[], int len) {
      ^~~~
In file included from /usr/include/c++/7/bits/move.h:54:0,
                 from /usr/include/c++/7/bits/nested_exception.h:40,
                 from /usr/include/c++/7/exception:143,
                 from /usr/include/c++/7/ios:39,
                 from /usr/include/c++/7/ostream:38,
                 from /usr/include/c++/7/iostream:39,
                 from Main.cc:1:
/usr/include/c++/7/type_traits:1468:12: note:                 template struct std::rank
     struct rank
            ^~~~