public MultilevelNode(int?_val) { val = _val; prev = null; next = null; child = null; }
public MultilevelNode(int?_val, MultilevelNode _prev) { val = _val; prev = _prev; next = null; child = null; }
public MultilevelNode(int?_val) { val = _val; prev = null; next = null; child = null; }
public MultilevelNode(int?_val, MultilevelNode _prev) { val = _val; prev = _prev; next = null; child = null; }