foo.cc:2:7: error: expected nested-name-specifier before 'nameapce'
    2 | using nameapce std;
      |       ^~~~~~~~
foo.cc: In function 'int find(int)':
foo.cc:12:26: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   12 |                 int mid=l+r>>1;
      |                         ~^~
foo.cc: In function 'int main()':
foo.cc:19:9: error: 'cin' was not declared in this scope; did you mean 'std::cin'?
   19 |         cin>>n>>m;
      |         ^~~
      |         std::cin
In file included from stdc++.h:75:
/nix/store/np14qqgvvnyna3vv640hmhi21flymiia-gcc-12.2.0/include/c++/12.2.0/iostream:60:18: note: 'std::cin' declared here
   60 |   extern istream cin;           /// Linked to standard input
      |                  ^~~
foo.cc:26:17: error: 'string' was not declared in this scope; did you mean 'std::string'?
   26 |                 string op;int x;
      |                 ^~~~~~
      |                 std::string
In file included from /nix/store/np14qqgvvnyna3vv640hmhi21flymiia-gcc-12.2.0/include/c++/12.2.0/iosfwd:39,
                 from /nix/store/np14qqgvvnyna3vv640hmhi21flymiia-gcc-12.2.0/include/c++/12.2.0/ios:38,
                 from /nix/store/np14qqgvvnyna3vv640hmhi21flymiia-gcc-12.2.0/include/c++/12.2.0/istream:38,
                 from /nix/store/np14qqgvvnyna3vv640hmhi21flymiia-gcc-12.2.0/include/c++/12.2.0/sstream:38,
                 from /nix/store/np14qqgvvnyna3vv640hmhi21flymiia-gcc-12.2.0/include/c++/12.2.0/complex:45,
                 from /nix/store/np14qqgvvnyna3vv640hmhi21flymiia-gcc-12.2.0/include/c++/12.2.0/ccomplex:39,
                 from stdc++.h:54:
/nix/store/np14qqgvvnyna3vv640hmhi21flymiia-gcc-12.2.0/include/c++/12.2.0/bits/stringfwd.h:77:33: note: 'std::string' declared here
   77 |   typedef basic_string<char>    string;
      |                                 ^~~~~~
foo.cc:27:22: error: 'op' was not declared in this scope
   27 |                 cin>>op>>x;
      |                      ^~
foo.cc:47:25: error: 'swap' was not declared in this scope
   47 |                         swap(a[pos],a[id[x]]);
      |                         ^~~~
foo.cc:47:25: note: suggested alternatives:
In file included from /nix/store/np14qqgvvnyna3vv640hmhi21flymiia-gcc-12.2.0/include/c++/12.2.0/regex:66,
                 from stdc++.h:110:
/nix/store/np14qqgvvnyna3vv640hmhi21flymiia-gcc-12.2.0/include/c++/12.2.0/bits/regex.h:2171:5: note:   'std::__cxx11::swap'
 2171 |     swap(match_results<_Bi_iter, _Alloc>& __lhs,
      |     ^~~~
In file included from /nix/store/np14qqgvvnyna3vv640hmhi21flymiia-gcc-12.2.0/include/c++/12.2.0/bits/exception_ptr.h:43,
                 from /nix/store/np14qqgvvnyna3vv640hmhi21flymiia-gcc-12.2.0/include/c++/12.2.0/exception:168,
                 from /nix/store/np14qqgvvnyna3vv640hmhi21flymiia-gcc-12.2.0/include/c++/12.2.0/ios:39:
/nix/store/np14qqgvvnyna3vv640hmhi21flymiia-gcc-12.2.0/include/c++/12.2.0/bits/move.h:196:5: note:   'std::swap'
  196 |     swap(_Tp& __a, _Tp& __b)
      |     ^~~~
/nix/store/np14qqgvvnyna3vv640hmhi21flymiia-gcc-12.2.0/include/c++/12.2.0/bits/exception_ptr.h:223:5: note:   'std::__exception_ptr::swap'
  223 |     swap(exception_ptr& __lhs, exception_ptr& __rhs)
      |     ^~~~
foo.cc:51:25: error: 'cout' was not declared in this scope; did you mean 'std::cout'?
   51 |                         cout<<query(id[x])-1<<endl;
      |                         ^~~~
      |                         std::cout
/nix/store/np14qqgvvnyna3vv640hmhi21flymiia-gcc-12.2.0/include/c++/12.2.0/iostream:61:18: note: 'std::cout' declared here
   61 |   extern ostream cout;          /// Linked to standard output
      |                  ^~~~
foo.cc:51:47: error: 'endl' was not declared in this scope; did you mean 'std::endl'?
   51 |                         cout<<query(id[x])-1<<endl;
      |                                               ^~~~
      |                                               std::endl
In file included from /nix/store/np14qqgvvnyna3vv640hmhi21flymiia-gcc-12.2.0/include/c++/12.2.0/istream:39:
/nix/store/np14qqgvvnyna3vv640hmhi21flymiia-gcc-12.2.0/include/c++/12.2.0/ostream:688:5: note: 'std::endl' declared here
  688 |     endl(basic_ostream<_CharT, _Traits>& __os)
      |     ^~~~
foo.cc:54:25: error: 'cout' was not declared in this scope; did you mean 'std::cout'?
   54 |                         cout<<a[find(x)]<<endl;
      |                         ^~~~
      |                         std::cout
/nix/store/np14qqgvvnyna3vv640hmhi21flymiia-gcc-12.2.0/include/c++/12.2.0/iostream:61:18: note: 'std::cout' declared here
   61 |   extern ostream cout;          /// Linked to standard output
      |                  ^~~~
foo.cc:54:43: error: 'endl' was not declared in this scope; did you mean 'std::endl'?
   54 |                         cout<<a[find(x)]<<endl;
      |                                           ^~~~
      |                                           std::endl
/nix/store/np14qqgvvnyna3vv640hmhi21flymiia-gcc-12.2.0/include/c++/12.2.0/ostream:688:5: note: 'std::endl' declared here
  688 |     endl(basic_ostream<_CharT, _Traits>& __os)
      |     ^~~~

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