/in/foo.cc: In function 'bool bfs()':
/in/foo.cc:44:29: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
 for( register int i = 0 ; i < linker[ now ].size() ; i++ )
                           ~~^~~~~~~~~~~~~~~~~~~~~~
/in/foo.cc: In function 'long long int dinic(int, long long int)':
/in/foo.cc:54:38: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
 for( register int i = cur[ now ] ; i < linker[ now ].size() ; i++ )
                                    ~~^~~~~~~~~~~~~~~~~~~~~~
/in/foo.cc: In function 'bool check(long long int)':
/in/foo.cc:77:14: error: reference to 'hash' is ambiguous
 addedge( s , hash[i][j] , x - a[i][j] ) , tot += x - a[i][j];
              ^~~~
/in/foo.cc:23:33: note: candidates are: int hash [42][42]
 int n , m , a[40 + 2][40 + 2] , hash[40 + 2][40 + 2] , r;
                                 ^~~~
In file included from /usr/include/c++/6/bits/basic_string.h:5643:0,
                 from /usr/include/c++/6/string:52,
                 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:1:
/usr/include/c++/6/bits/functional_hash.h:58:12: note:                 template<class _Tp> struct std::hash
     struct hash;
            ^~~~
/in/foo.cc:78:23: error: reference to 'hash' is ambiguous
 if( i != 1 ) addedge( hash[i][j] , hash[i - 1][j] , inf );
                       ^~~~
/in/foo.cc:23:33: note: candidates are: int hash [42][42]
 int n , m , a[40 + 2][40 + 2] , hash[40 + 2][40 + 2] , r;
                                 ^~~~
In file included from /usr/include/c++/6/bits/basic_string.h:5643:0,
                 from /usr/include/c++/6/string:52,
                 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:1:
/usr/include/c++/6/bits/functional_hash.h:58:12: note:                 template<class _Tp> struct std::hash
     struct hash;
            ^~~~
/in/foo.cc:78:36: error: reference to 'hash' is ambiguous
 if( i != 1 ) addedge( hash[i][j] , hash[i - 1][j] , inf );
                                    ^~~~
/in/foo.cc:23:33: note: candidates are: int hash [42][42]
 int n , m , a[40 + 2][40 + 2] , hash[40 + 2][40 + 2] , r;
                                 ^~~~
In file included from /usr/include/c++/6/bits/basic_string.h:5643:0,
                 from /usr/include/c++/6/string:52,
                 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:1:
/usr/include/c++/6/bits/functional_hash.h:58:12: note:                 template<class _Tp> struct std::hash
     struct hash;
            ^~~~
/in/foo.cc:79:23: error: reference to 'hash' is ambiguous
 if( i != n ) addedge( hash[i][j] , hash[i + 1][j] , inf );
                       ^~~~
/in/foo.cc:23:33: note: candidates are: int hash [42][42]
 int n , m , a[40 + 2][40 + 2] , hash[40 + 2][40 + 2] , r;
                                 ^~~~
In file included from /usr/include/c++/6/bits/basic_string.h:5643:0,
                 from /usr/include/c++/6/string:52,
                 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:1:
/usr/include/c++/6/bits/functional_hash.h:58:12: note:                 template<class _Tp> struct std::hash
     struct hash;
            ^~~~
/in/foo.cc:79:36: error: reference to 'hash' is ambiguous
 if( i != n ) addedge( hash[i][j] , hash[i + 1][j] , inf );
                                    ^~~~
/in/foo.cc:23:33: note: candidates are: int hash [42][42]
 int n , m , a[40 + 2][40 + 2] , hash[40 + 2][40 + 2] , r;
                                 ^~~~
In file included from /usr/include/c++/6/bits/basic_string.h:5643:0,
                 from /usr/include/c++/6/string:52,
                 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:1:
/usr/include/c++/6/bits/functional_hash.h:58:12: note:                 template<class _Tp> struct std::hash
     struct hash;
            ^~~~
/in/foo.cc:80:23: error: reference to 'hash' is ambiguous
 if( j != 1 ) addedge( hash[i][j] , hash[i][j - 1] , inf );
                       ^~~~
/in/foo.cc:23:33: note: candidates are: int hash [42][42]
 int n , m , a[40 + 2][40 + 2] , hash[40 + 2][40 + 2] , r;
                                 ^~~~
In file included from /usr/include/c++/6/bits/basic_string.h:5643:0,
                 from /usr/include/c++/6/string:52,
                 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:1:
/usr/include/c++/6/bits/functional_hash.h:58:12: note:                 template<class _Tp> struct std::hash
     struct hash;
            ^~~~
/in/foo.cc:80:36: error: reference to 'hash' is ambiguous
 if( j != 1 ) addedge( hash[i][j] , hash[i][j - 1] , inf );
                                    ^~~~
/in/foo.cc:23:33: note: candidates are: int hash [42][42]
 int n , m , a[40 + 2][40 + 2] , hash[40 + 2][40 + 2] , r;
                                 ^~~~
In file included from /usr/include/c++/6/bits/basic_string.h:5643:0,
                 from /usr/include/c++/6/string:52,
                 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:1:
/usr/include/c++/6/bits/functional_hash.h:58:12: note:                 template<class _Tp> struct std::hash
     struct hash;
            ^~~~
/in/foo.cc:81:23: error: reference to 'hash' is ambiguous
 if( j != m ) addedge( hash[i][j] , hash[i][j + 1] , inf );
                       ^~~~
/in/foo.cc:23:33: note: candidates are: int hash [42][42]
 int n , m , a[40 + 2][40 + 2] , hash[40 + 2][40 + 2] , r;
                                 ^~~~
In file included from /usr/include/c++/6/bits/basic_string.h:5643:0,
                 from /usr/include/c++/6/string:52,
                 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:1:
/usr/include/c++/6/bits/functional_hash.h:58:12: note:                 template<class _Tp> struct std::hash
     struct hash;
            ^~~~
/in/foo.cc:81:36: error: reference to 'hash' is ambiguous
 if( j != m ) addedge( hash[i][j] , hash[i][j + 1] , inf );
                                    ^~~~
/in/foo.cc:23:33: note: candidates are: int hash [42][42]
 int n , m , a[40 + 2][40 + 2] , hash[40 + 2][40 + 2] , r;
                                 ^~~~
In file included from /usr/include/c++/6/bits/basic_string.h:5643:0,
                 from /usr/include/c++/6/string:52,
                 f