compilation error

[03343]

23tree.cpp:456:27: error: no matching constructor for initialization of 'usefulData'
usefulData s1 = insert(root, d, p);
^ ~~~~~~~~~~~~~~~~~~
23tree.cpp:1168:19: note: in instantiation of member function 'two3Tree::insert' requested here
tree1.insert(data);
^
23tree.cpp:31:5: note: candidate constructor not viable: no known conversion from 'usefulData' to 'two3node ' for 1st
argument
usefulData (two3node c)
^
23tree.cpp:57:5: note: candidate constructor not viable: expects an l-value for 1st argument
usefulData(usefulData & otherusefulData)
^
23tree.cpp:25:5: note: candidate constructor not viable: requires 0 arguments, but 1 was provided
usefulData()
^
23tree.cpp:37:5: note: candidate constructor not viable: requires 2 arguments, but 1 was provided
usefulData (two3node* c, T m)
^
23tree.cpp:497:13: error: no viable constructor returning object of type 'usefulData'
return (NULL);
^ ~~~~~~
23tree.cpp:456:32: note: in instantiation of member function 'two3Tree::insert' requested here
usefulData s1 = insert(root, d, p);
^
23tree.cpp:1168:19: note: in instantiation of member function 'two3Tree::insert' requested here
tree1.insert(data);
^
23tree.cpp:31:5: note: candidate constructor not viable: no known conversion from 'usefulData' to 'two3node ' for 1st
argument
usefulData (two3node c)
^
23tree.cpp:57:5: note: candidate constructor not viable: expects an l-value for 1st argument
usefulData(usefulData & otherusefulData)
^
23tree.cpp:25:5: note: candidate constructor not viable: requires 0 arguments, but 1 was provided
usefulData()
^
23tree.cpp:37:5: note: candidate constructor not viable: requires 2 arguments, but 1 was provided
usefulData (two3node* c, T m)
^
23tree.cpp:811:32: error: no viable overloaded '='
s1 = Delete (r -> left, d, r);
~~ ^ ~~~~~~~~~~~~~~~~~~~~~~~~
23tree.cpp:786:9: note: in instantiation of member function 'two3Tree::Delete' requested here
Delete(root,d,p);
^
23tree.cpp:1179:19: note: in instantiation of member function 'two3Tree::deleteNode' requested here
tree1.deleteNode(data);
^
23tree.cpp:45:19: note: candidate function not viable: expects an l-value for 1st argument
usefulData operator = (usefulData & otherusefulData)
^
23tree.cpp:854:21: error: no viable constructor returning object of type 'usefulData'
return (NULL);
^ ~~~~~~
23tree.cpp:31:5: note: candidate constructor not viable: no known conversion from 'usefulData' to 'two3node ' for 1st
argument
usefulData (two3node c)
^
23tree.cpp:57:5: note: candidate constructor not viable: expects an l-value for 1st argument
usefulData(usefulData & otherusefulData)
^
23tree.cpp:25:5: note: candidate constructor not viable: requires 0 arguments, but 1 was provided
usefulData()
^
23tree.cpp:37:5: note: candidate constructor not viable: requires 2 arguments, but 1 was provided
usefulData (two3node* c, T m)
^
23tree.cpp:863:28: error: no viable overloaded '='
s1 = rotateRight(p,r,s1.midValue,s1.child); //MidValue is just a dummy here. Used to compl...
~~ ^ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
23tree.cpp:45:19: note: candidate function not viable: expects an l-value for 1st argument
usefulData operator = (usefulData & otherusefulData)
^
23tree.cpp:996:28: error: no viable overloaded '='
s1 = rotateRight(p,r,s1.midValue,NULL); //MidValue is just a dummy here. Used to compl...
~~ ^ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
23tree.cpp:45:19: note: candidate function not viable: expects an l-value for 1st argument
usefulData operator = (usefulData & otherusefulData)
^
23tree.cpp:1012:13: error: no viable constructor returning object of type 'usefulData'
return (NULL);
^ ~~~~~~
23tree.cpp:31:5: note: candidate constructor not viable: no known conversion from 'usefulData' to 'two3node ' for 1st
argument
usefulData (two3node c)
^
23tree.cpp:57:5: note: candidate constructor not viable: expects an l-value for 1st argument
usefulData(usefulData & otherusefulData)
^
23tree.cpp:25:5: note: candidate constructor not viable: requires 0 arguments, but 1 was provided
usefulData()
^
23tree.cpp:37:5: note: candidate constructor not viable: requires 2 arguments, but 1 was provided
usefulData (two3node* c, T m)
^
23tree.cpp:324:9: error: no viable constructor returning object of type 'usefulData'
return (NULL);
^ ~~~~~~
23tree.cpp:863:31: note: in instantiation of member function 'two3Tree::rotateRight' requested here
s1 = rotateRight(p,r,s1.midValue,s1.child); //MidValue is just a dummy here. Used to compl...
^
23tree.cpp:786:9: note: in instantiation of member function 'two3Tree::Delete' requested here
Delete(root,d,p);
^
23tree.cpp:1179:19: note: in instantiation of member function 'two3Tree::deleteNode' requested here
tree1.deleteNode(data);
^
23tree.cpp:31:5: note: candidate constructor not viable: no known conversion from 'usefulData' to 'two3node ' for 1st
argument
usefulData (two3node c)
^
23tree.cpp:57:5: note: candidate constructor not viable: expects an l-value for 1st argument
usefulData(usefulData & otherusefulData)
^
23tree.cpp:25:5: note: candidate constructor not viable: requires 0 arguments, but 1 was provided
usefulData()
^
23tree.cpp:37:5: note: candidate constructor not viable: requires 2 arguments, but 1 was provided
usefulData (two3node* c, T m)
^
8 errors generated.