foo.cc:6:43: error: 'tree_order_statistic_node_update' was not declared in this scope
    6 | tree<int,null_type,less<int> ,rb_tree_tag,tree_order_statistic_node_update> T;
      |                                           ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
foo.cc:6:75: error: template argument 5 is invalid
    6 | tree<int,null_type,less<int> ,rb_tree_tag,tree_order_statistic_node_update> T;
      |                                                                           ^

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