View Compilation Error

0_0_37301835_20028.cpp: In function 'int main()':
0_0_37301835_20028.cpp:51:10: error: expected unqualified-id before '[' token
     auto [e, flag] = q.top(); q.pop();
          ^
0_0_37301835_20028.cpp:52:19: error: 'e' was not declared in this scope
     int f1 = find(e.u), f2 = find(e.v);
                   ^
0_0_37301835_20028.cpp:53:15: error: 'f2' was not declared in this scope
     if (f1 != f2) {
               ^
0_0_37301835_20028.cpp:55:10: error: 'flag' was not declared in this scope
      cnt[flag]++;
          ^