/in/foo.cc: In function 'void dfs2(int)':
/in/foo.cc:6:37: error: 'typeof' was not declared in this scope
 #define FOR(i,v)  for(typeof(v.end())i=v.begin();i!=v.end();++i)
                                     ^
/in/foo.cc:26:5: note: in expansion of macro 'FOR'
     FOR(i,e[u])
     ^~~
/in/foo.cc:26:9: error: 'i' was not declared in this scope
     FOR(i,e[u])
         ^
/in/foo.cc:6:50: note: in definition of macro 'FOR'
 #define FOR(i,v)  for(typeof(v.end())i=v.begin();i!=v.end();++i)
                                                  ^
/in/foo.cc:6:37: error: 'typeof' was not declared in this scope
 #define FOR(i,v)  for(typeof(v.end())i=v.begin();i!=v.end();++i)
                                     ^
/in/foo.cc:31:5: note: in expansion of macro 'FOR'
     FOR(i,e[u])
     ^~~
/in/foo.cc:31:9: error: 'i' was not declared in this scope
     FOR(i,e[u])
         ^
/in/foo.cc:6:50: note: in definition of macro 'FOR'
 #define FOR(i,v)  for(typeof(v.end())i=v.begin();i!=v.end();++i)
                                                  ^