/in/foo.cc: In function 'void Build(int)':
/in/foo.cc:25:17: error: 'swap' was not declared in this scope
         swap(x,y);x[sa[1]]=1;p=2;
                 ^
/in/foo.cc:25:17: note: suggested alternatives:
In file included from /usr/include/c++/6/string:52:0,
                 from /usr/include/c++/6/bits/locale_classes.h:40,
                 from /usr/include/c++/6/bits/ios_base.h:41,
                 from /usr/include/c++/6/ios:42,
                 from /usr/include/c++/6/ostream:38,
                 from /usr/include/c++/6/iostream:39,
                 from /in/foo.cc:3:
/usr/include/c++/6/bits/basic_string.h:5302:5: note:   'std::swap'
     swap(basic_string<_CharT, _Traits, _Alloc>& __lhs,
     ^~~~
In file included from /usr/include/c++/6/exception:172:0,
                 from /usr/include/c++/6/ios:39,
                 from /usr/include/c++/6/ostream:38,
                 from /usr/include/c++/6/iostream:39,
                 from /in/foo.cc:3:
/usr/include/c++/6/bits/exception_ptr.h:164:5: note:   'std::__exception_ptr::swap'
     swap(exception_ptr& __lhs, exception_ptr& __rhs)
     ^~~~
In file included from /usr/include/c++/6/bits/nested_exception.h:40:0,
                 from /usr/include/c++/6/exception:173,
                 from /usr/include/c++/6/ios:39,
                 from /usr/include/c++/6/ostream:38,
                 from /usr/include/c++/6/iostream:39,
                 from /in/foo.cc:3:
/usr/include/c++/6/bits/move.h:179:5: note:   'std::swap'
     swap(_Tp& __a, _Tp& __b)
     ^~~~
/in/foo.cc: In function 'int main()':
/in/foo.cc:46:5: warning: this 'for' clause does not guard... [-Wmisleading-indentation]
     for(int i=1;i<=n;++i)++s[i];Build(1000001);
     ^~~
/in/foo.cc:46:33: note: ...this statement, but the latter is misleadingly indented as if it is guarded by the 'for'
     for(int i=1;i<=n;++i)++s[i];Build(1000001);
                                 ^~~~~
/in/foo.cc:52:38: error: 'max' was not declared in this scope
         if(i>t)ans=max(ans,h[q[head]]);
                                      ^
/in/foo.cc:52:38: note: suggested alternative:
In file included from /usr/include/c++/6/algorithm:62:0,
                 from /in/foo.cc:4:
/usr/include/c++/6/bits/stl_algo.h:3465:5: note:   'std::max'
     max(initializer_list<_Tp> __l, _Compare __comp)
     ^~~