View Compilation Error

0_0_36879237_3959.cpp: In function 'int main()':
0_0_36879237_3959.cpp:126:14: error: 'a' was not declared in this scope
     sort(all(a));    
              ^
0_0_36879237_3959.cpp:46:16: note: in definition of macro 'all'
 #define all(s) s.begin(),s.end()
                ^