/in/foo.cc: In function 'void Prework()':
/in/foo.cc:52:3: warning: this 'if' clause does not guard... [-Wmisleading-indentation]
   if(top[i]!=i) continue;U[i].pb(i);D[i].pb(i);
   ^~
/in/foo.cc:52:26: note: ...this statement, but the latter is misleadingly indented as if it is guarded by the 'if'
   if(top[i]!=i) continue;U[i].pb(i);D[i].pb(i);
                          ^